"Gearbox fault," chattering noise, and popping out of gear
#21
I did drain another 4 quarts back out and refilled it again after maybe 15 miles of driving. It wasn't quite as black as chocolate syrup thistime. It was more like good strong coffee. It had bit of a reddish tint, and I could see through the stream as it poured out of the trans. But still very dark.
I hope a good fluid change over is all I need.
I hope a good fluid change over is all I need.
#22
Well, I took it for another quick drive to see how she's doing, and to warm it up for another partial fluid change.
All was well, and the trans was feeling better than ever. Then on the second to last corner before returning to my house "Gearbox fault" was back. It stayed in 2nd gear the rest of the way home, maybe 1/2 mile. I checked the codes - P0730 again, and P1632. Incorrect gear ratio, and some sort of communications error.
Also as I was slowing down for the corner right after the "gearbox fault" message came up the ABS kicked on and the ABS light lit up where there was no call for it at all. Thinking back, I have had several random ABS / Stability / Traction Assist messages come up, that go away after restarting the car.
I wonder if I have an intermittent wheel speed sensor that is causing this? I don't understand how the trans can act so good for a while, then completely flake out then heal its self on a restart unless it is an electrical sort of issue.
All was well, and the trans was feeling better than ever. Then on the second to last corner before returning to my house "Gearbox fault" was back. It stayed in 2nd gear the rest of the way home, maybe 1/2 mile. I checked the codes - P0730 again, and P1632. Incorrect gear ratio, and some sort of communications error.
Also as I was slowing down for the corner right after the "gearbox fault" message came up the ABS kicked on and the ABS light lit up where there was no call for it at all. Thinking back, I have had several random ABS / Stability / Traction Assist messages come up, that go away after restarting the car.
I wonder if I have an intermittent wheel speed sensor that is causing this? I don't understand how the trans can act so good for a while, then completely flake out then heal its self on a restart unless it is an electrical sort of issue.
#23
I did some digging around on the net, and found this on a Chrysler board regarding the NAG1 trans. It sounds just like my symptoms with the trans going into neutral and setting the P0730 code.
Also worst case I checked a couple of local junkyards. It looks like there are several lower mileage (~75k mile) used transmissions from XJR's nearby available for about $1,000.
P0730-INCORRECT GEAR RATIO
For a complete wiring diagram Refer to Section 8W
Theory of Operation
The Transmission Control Module (TCM) constantly calculates the transmission ratio based on the input speed sensor 1 and 2 (N2-N3) signals and the calculated output shaft speed. The intent of this diagnostic is to detect if the transmission is trying to mechanically shift into a different gear than the TCM intends.
NOTE: The transmission control module is programmed to immediately place the transmission into neutral if P0730 or P1731 codes are set. These codes indicate that the transmission experienced an unknown or incorrect gear ratio. Placing the transmission in neutral prevents potential catastrophic failure. When this occurs, the transmission will remain in neutral until the vehicle slows to 29 Km/h (18 mph).
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)
Diagnostic Test
1. CHECK IF ABS DTCS ARE PRESENT
With the scan tool, check for ABS DTCs.
Are there any ABS DTCs present?
Yes
2. CHECK IF TRANSMISSION SOLENOID DTCS ARE PRESENT
With the scan tool, check for other transmission DTCs.
Are there any transmission solenoid, speed sensor and/or any other transmission electrical related DTCs present?
Yes
3. CHECK TRANSMISSION FLUID LEVEL
NOTE: Low fluid level can be the cause of many transmission problems. Visually inspect the transmission and cooler lines for leakage and repair as necessary and adjust the fluid level per the Service Information. If no visual leaks are observed and the vehicle has obtained over 1610 km (1000 miles) from either new or transmission service, a fluid level check is unnecessary.
Check the transmission fluid level and condition per the Service Information. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE)
Is the fluid level and condition correct?
Yes
4. CHECK ENVIRONMENTAL DATA
With the scan tool, check environmental data for P1731.
Did the environmental data show the code setting during a 3-4 upshift or 4-3 downshift?
Yes
5. CHECK FOR INTERNAL TRANSMISSION PROBLEM
Check for an internal Transmission mechanical problem(s).
Remove the Transmission Oil Pan and inspect for excessive debris or a plugged Transmission Oil Filter. Refer to 21 - TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE.
Inspect the valve body for foreign material, starting with the four valves associated with the shift described in the environmental data (shift pressure, holding, overlap, command), and continue on to the other valves.
This DTC is usually set due to an internal transmission problem such as but not limited to: XXXXX XXXXX valve and/or contamination in the valve body, broken springs, leaking clutch seals, dislodged or broken snap ring etc.
Inspect the internal transmission, Refer to 21- AUTOMATIC TRANSMISSION - AUTOMATIC TRANSMISSION NAG1/SERVICE INFORMATION for the appropriate service procedure(s) and other possible causes.
Were there any problems found?
Yes
For a complete wiring diagram Refer to Section 8W
Theory of Operation
The Transmission Control Module (TCM) constantly calculates the transmission ratio based on the input speed sensor 1 and 2 (N2-N3) signals and the calculated output shaft speed. The intent of this diagnostic is to detect if the transmission is trying to mechanically shift into a different gear than the TCM intends.
NOTE: The transmission control module is programmed to immediately place the transmission into neutral if P0730 or P1731 codes are set. These codes indicate that the transmission experienced an unknown or incorrect gear ratio. Placing the transmission in neutral prevents potential catastrophic failure. When this occurs, the transmission will remain in neutral until the vehicle slows to 29 Km/h (18 mph).
- When Monitored: Engine rpm greater than 450 rpm, no N2 - N3 input speed sensor errors present, no gear selector lever errors present, no ABS system errors, and vehicle speed above 10 Km/h (6 mph).
- Set Condition: No shifting operation and actual gear differs from the target gear. No shifting operation - actual (calculated) gear differs from the target (expected) gear, no plausible gear is calculated, actual (calculated) turbine speed is greater than 300 rpm or calculated transmission ratio is above threshold. During an Upshift - actual (calculated) gear is less than target (expected) gear. During Downshift - actual (calculated) gear is greater than target (expected) gear.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)
Diagnostic Test
1. CHECK IF ABS DTCS ARE PRESENT
With the scan tool, check for ABS DTCs.
Are there any ABS DTCs present?
Yes
- Refer to 5 - BRAKES - ELECTRICAL DIAGNOSTICS category and perform the appropriate symptom(s).
- Go to 2
2. CHECK IF TRANSMISSION SOLENOID DTCS ARE PRESENT
With the scan tool, check for other transmission DTCs.
Are there any transmission solenoid, speed sensor and/or any other transmission electrical related DTCs present?
Yes
- Refer to the sympXXXXX XXXXXst and perform the appropriate symptom(s).
- Go to 3
3. CHECK TRANSMISSION FLUID LEVEL
NOTE: Low fluid level can be the cause of many transmission problems. Visually inspect the transmission and cooler lines for leakage and repair as necessary and adjust the fluid level per the Service Information. If no visual leaks are observed and the vehicle has obtained over 1610 km (1000 miles) from either new or transmission service, a fluid level check is unnecessary.
Check the transmission fluid level and condition per the Service Information. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE)
Is the fluid level and condition correct?
Yes
- Go to 4
- Correct the fluid level per the Service Information
- Perform NAG1 TRANSMISSION VERIFICATION TEST.(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)
4. CHECK ENVIRONMENTAL DATA
With the scan tool, check environmental data for P1731.
Did the environmental data show the code setting during a 3-4 upshift or 4-3 downshift?
Yes
- NOTE: Debris may enter through the vents in the top of the valvebody. The debris can be a very small sliver that is visibly unnoticable unless flushing onto a fine filter paper. The debris has the potential to stick the 3-4 Shift Pressure or 3-4 Holding valves. If either valve is stuck during a 3-4 upshift or 4-3 downshift, a shift flare, bump shift, harsh shift, or neutraling out will occur.
- Flush and clean the Valve Body per the Service Information. Pay particular attention to the 3-4 shift pressure and 3-4 holding valve. Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/ELECTROHYDRAULIC UNIT - CLEANING.
- Perform NAG1 TRANSMISSION VERIFICATION TEST.(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)
- Go to 5
5. CHECK FOR INTERNAL TRANSMISSION PROBLEM
Check for an internal Transmission mechanical problem(s).
Remove the Transmission Oil Pan and inspect for excessive debris or a plugged Transmission Oil Filter. Refer to 21 - TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE.
Inspect the valve body for foreign material, starting with the four valves associated with the shift described in the environmental data (shift pressure, holding, overlap, command), and continue on to the other valves.
This DTC is usually set due to an internal transmission problem such as but not limited to: XXXXX XXXXX valve and/or contamination in the valve body, broken springs, leaking clutch seals, dislodged or broken snap ring etc.
Inspect the internal transmission, Refer to 21- AUTOMATIC TRANSMISSION - AUTOMATIC TRANSMISSION NAG1/SERVICE INFORMATION for the appropriate service procedure(s) and other possible causes.
Were there any problems found?
Yes
- Repair as necessary per the Service Information.
- Perform NAG1 TRANSMISSION VERIFICATION TEST.(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)
- If no internal transmission mechanical problems are found, using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the TCM per the Service Information. Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE for the appropriate service procedure
Also worst case I checked a couple of local junkyards. It looks like there are several lower mileage (~75k mile) used transmissions from XJR's nearby available for about $1,000.
Last edited by Andy94SC; 05-23-2011 at 08:38 PM.
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Sean B (04-12-2012)
#25
I did take it for a fairly gentle drive, and after about 20 normal miles she went into neutral while cruising steady at about 45MPH.
I've noticed that's when it seems to act up the most, just at a light cruise. If you hammer it, it performs beautifully. It also doesn't seem to do anything wrong when in Sport mode.
I think it may be time to turn over to an expert, but I am dreading that.
I found Chrysler's service documents on this trans. Interesting reading, but I wouldn't take it as gospel on the Jaguar version...
http://www.hotrodlane.cc/New%20HEMI%...mi%20trans.pdf
I've noticed that's when it seems to act up the most, just at a light cruise. If you hammer it, it performs beautifully. It also doesn't seem to do anything wrong when in Sport mode.
I think it may be time to turn over to an expert, but I am dreading that.
I found Chrysler's service documents on this trans. Interesting reading, but I wouldn't take it as gospel on the Jaguar version...
http://www.hotrodlane.cc/New%20HEMI%...mi%20trans.pdf
Last edited by Andy94SC; 05-23-2011 at 08:50 PM.
#26
If she shifts and runs through the entire range of gears and across the entire temperature range and then occasionally fails, chances are you have electronic issue, maybe control module, or some sensors. It is hard to advise, but our transmissions are literally indestructible.
Get it to work already, so I could tell you that your supercharger oil also needs replaced...
Get it to work already, so I could tell you that your supercharger oil also needs replaced...
#27
Too late, I already replaced the supercharger oil.
I found an actual Jaguar W5A580 diagnostic document online, and possibly another hint. The actual definition of my P1632 code is "corrupt front wheel speed sensor CAN message"
W5A-580.pdf
Maybe I should try swapping in a new wheel speed sensor?
I found an actual Jaguar W5A580 diagnostic document online, and possibly another hint. The actual definition of my P1632 code is "corrupt front wheel speed sensor CAN message"
W5A-580.pdf
Maybe I should try swapping in a new wheel speed sensor?
#29
The W5A580 has very fine valve body oil passages, and the new tranny fluid may still be cleaning out the passages by mixing with the old gum and varnish.
Longer hot drives between flushes may be more beneficial to you in cleaning out the crud than many short drive and flush cycles.
The Chrysler TSB for the NAG1 covering moisture induced slippage calls for three complete flushes. And that is a warranty job. You know that they aren't going to foot the bill for three complete flushes unless they think it is absolutely required.
In case anybody is wondering:
The TSB covers slippage induced by water contamination of the transmission fluid in the NAG1 at concentrations of one half of one percent.
The water ingress is via the dipstick tube to transmission case interface.
The fix to be applied is thorough cleaning of the surrounding area and application of RTV silicone around the external surface of the interface. AKA: gob the stuff on.
Last edited by plums; 05-23-2011 at 10:10 PM.
#30
Well I have been getting other indications of wheel speed sensor problems aside from the trans issues. The trans fluid probably isn't going to help the ABS/Stability/traction failures.
You do have a point on going for longer drives. When I was flushing things out this weekend I was running about a 10 mile loop around my house between drainings and fillings.
I'm not sure I have slippage issues based on how the trans seems to feel. From reading the materials linked above it appears that my trans has been going into a failsafe mode. That may be caused by slippage, but it might also be caused other things, such as average wheel speed not matching the TCM's calculation of vehicle speed.
One thing that bothers me is that I never saw the trans issues until right after I fixed the front wheel bearing and bent tie rod. I don't think anything got damaged while doing that repair, I was pretty careful. I have since taken a look at the sensors, and wiring, and everything looks OK. I am wondering if somehow jacking up the front of the car let some debris float backwards in the trans or something?
You do have a point on going for longer drives. When I was flushing things out this weekend I was running about a 10 mile loop around my house between drainings and fillings.
I'm not sure I have slippage issues based on how the trans seems to feel. From reading the materials linked above it appears that my trans has been going into a failsafe mode. That may be caused by slippage, but it might also be caused other things, such as average wheel speed not matching the TCM's calculation of vehicle speed.
One thing that bothers me is that I never saw the trans issues until right after I fixed the front wheel bearing and bent tie rod. I don't think anything got damaged while doing that repair, I was pretty careful. I have since taken a look at the sensors, and wiring, and everything looks OK. I am wondering if somehow jacking up the front of the car let some debris float backwards in the trans or something?
Last edited by Andy94SC; 05-24-2011 at 08:06 AM.
#32
Here's the weekly update.
I found a local guy parting out a 2001 XJ8, and scored a pair of used wheel speed sensors for $50.
Tonight was the first time I have driven the car all week. I swapped the front passenger side wheel speed sensor with one of my newly acquired ones and drove 3 miles before "Gearbox fault" appeared.
I pulled over and swapped the front drivers side sensor out, then drove 25 miles with no problems yet.
Fingers crossed.
I found a local guy parting out a 2001 XJ8, and scored a pair of used wheel speed sensors for $50.
Tonight was the first time I have driven the car all week. I swapped the front passenger side wheel speed sensor with one of my newly acquired ones and drove 3 miles before "Gearbox fault" appeared.
I pulled over and swapped the front drivers side sensor out, then drove 25 miles with no problems yet.
Fingers crossed.
#33
I'm not sure I should declare victory yet, but I've put on another 50 - 60 miles over 3-4 short trips without any hiccups from the trans since swapping the drivers side wheel speed sensor.
Also, I've heard the chattering noise a few more times. Sometimes it seems to correspond to shifts, or to throttle position, sometimes not. Sometimes I can make it happen on right hand turns, and go away by turning back straight, sometimes not.
Yesterday I was going quite slow on a back road with the windows down and heard it very clearly. So I started kind of swerving back and forth, making it come and go, trying to figure it out. Finally I stuck my head partly out the window while driving. Then I could definitely tell it was coming from the left rear wheel, NOT under the car as it appears from inside the car. The trans has been innocent of making odd noises, but I might have another wheel bearing to replace.
I may swap out some more fluid in the trans today and see how that looks, but I'm feeling pretty good about it now - and no trips to the dealer, yet.
Also, I've heard the chattering noise a few more times. Sometimes it seems to correspond to shifts, or to throttle position, sometimes not. Sometimes I can make it happen on right hand turns, and go away by turning back straight, sometimes not.
Yesterday I was going quite slow on a back road with the windows down and heard it very clearly. So I started kind of swerving back and forth, making it come and go, trying to figure it out. Finally I stuck my head partly out the window while driving. Then I could definitely tell it was coming from the left rear wheel, NOT under the car as it appears from inside the car. The trans has been innocent of making odd noises, but I might have another wheel bearing to replace.
I may swap out some more fluid in the trans today and see how that looks, but I'm feeling pretty good about it now - and no trips to the dealer, yet.
#36
Ah Gearbox Fault, my dear friend, I see you've returned. I hope you had a nice vacation.
Yep after a couple hundred miles of trouble free driving it came back yesterday. It's obviously a loose connection somewhere, and I suspect the front left wheel speed sensor wiring, since it went away for quite a while after I disturbed it.
Yesterday I was driving on a particularly bumpy road, and teh ASC went active and slowed the car for no reason. Then on a particularly good bump it went into nuetral, and at the exact same time I got the lights, and check ABS/Stability/Traction messages.
I got it home, shut of off for a couple hours, then restarted it and jiggled as much of the wheel speed sensor wiring I could while it was parked, but did not get any warnings to return. I unclipped and reseated the big connector to the ABS module too.
If it comes back I think I'll start with replacing that front wheel speed harness.
Yep after a couple hundred miles of trouble free driving it came back yesterday. It's obviously a loose connection somewhere, and I suspect the front left wheel speed sensor wiring, since it went away for quite a while after I disturbed it.
Yesterday I was driving on a particularly bumpy road, and teh ASC went active and slowed the car for no reason. Then on a particularly good bump it went into nuetral, and at the exact same time I got the lights, and check ABS/Stability/Traction messages.
I got it home, shut of off for a couple hours, then restarted it and jiggled as much of the wheel speed sensor wiring I could while it was parked, but did not get any warnings to return. I unclipped and reseated the big connector to the ABS module too.
If it comes back I think I'll start with replacing that front wheel speed harness.
#38
Well since that last posting I removed the drivers side wheel speed jumper and soldered the wiring to the terminals at both ends. I put on a good couple hundred problem free miles.
But just now on the way home from a BBQ, about 25 miles from home I got the gearbox fault message, but no other symptoms. I pulled over and restarted the car and made it home without any other incidents.
I guess tomorrow I'll pull the passenger side and solder those as well. Then I could try swapping out one of the rear sensors... But the code I got did indicate front... Maybe it's time to look at the ABS controller...
Megawatt, If you find some cure let me know. I'm going to keep posting on this thread until mine is gone, so it may turn out to be a VERY long thread.
But just now on the way home from a BBQ, about 25 miles from home I got the gearbox fault message, but no other symptoms. I pulled over and restarted the car and made it home without any other incidents.
I guess tomorrow I'll pull the passenger side and solder those as well. Then I could try swapping out one of the rear sensors... But the code I got did indicate front... Maybe it's time to look at the ABS controller...
Megawatt, If you find some cure let me know. I'm going to keep posting on this thread until mine is gone, so it may turn out to be a VERY long thread.
Last edited by Andy94SC; 06-11-2011 at 05:42 PM.
#39
I'm sure some of you may have tired of seeing this thread floating around, but a couple things came up this weekend.
I took a trip to my parents place on Saturday, and back this evening, about 350 miles round trip. No trans hiccups at all.
However I still think the issue is lurking, as I haven't really fixed anything since the last time it jumped out of gear and gave me the warning messages on the way back from the BBQ last weekend. What I DID notice during the ride up was with the cruise control.
I had not used the cruise control on this car before this weekend, but I did set it on the ride up. I didn't used it for very long though, because every other bump I hit made the car surge forward. I'm thinking this is also the wheel speed sensor. I figure if it drops out momentarily on a bump then the car thinks it has slowed, and tries to speed up. As I said I never got a gearbox fault, or any stability / ABS warnings, so maybe it has to drop out for longer periods of time for those issues to become apparent.
Also, I've got a tool at my disposal which should tell me EXACTLY which wheel speed sensor is acting up. That should help narrow it down quite a bit. I don't know why I didn't think to try it before, more information tomorrow - Enter the Vehicle Spy .
I took a trip to my parents place on Saturday, and back this evening, about 350 miles round trip. No trans hiccups at all.
However I still think the issue is lurking, as I haven't really fixed anything since the last time it jumped out of gear and gave me the warning messages on the way back from the BBQ last weekend. What I DID notice during the ride up was with the cruise control.
I had not used the cruise control on this car before this weekend, but I did set it on the ride up. I didn't used it for very long though, because every other bump I hit made the car surge forward. I'm thinking this is also the wheel speed sensor. I figure if it drops out momentarily on a bump then the car thinks it has slowed, and tries to speed up. As I said I never got a gearbox fault, or any stability / ABS warnings, so maybe it has to drop out for longer periods of time for those issues to become apparent.
Also, I've got a tool at my disposal which should tell me EXACTLY which wheel speed sensor is acting up. That should help narrow it down quite a bit. I don't know why I didn't think to try it before, more information tomorrow - Enter the Vehicle Spy .
#40