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I measures 1.2 M ohm on TCM plug between 14 and 42.
I measured 1.3 M ohm on TCM plug between 16 and 44.
are you sure it is not suppose to be 1300 K ohm on the speed sensor??
Moving over to the throttle body I will check the raising resistance now. also checking EM81 - 24 to ground. Will let you know what I find out.
Thanks,
For a assumed hall effect sensor that is high as an example other then my observations from other examples . But since they both " fundamentally " read the same and you have a code on only 1 you can assume both sensors are good other then the connections . I can be wrong on my meter scale observations .
Last edited by Lady Penelope; 12-27-2017 at 08:27 PM.
Lady Penelope,
What is the Papa Indy connector you are talking about, please explain so I can understand
The Papa Indy 1 connector would be easier ( look for connector corrosion and clean ) at pin 14 through 3 and pin 14 through 1.
Thanks,
Last edited by Don B; 01-07-2018 at 10:11 PM.
Reason: change Don to Lady P
To Lady P or Don,
I am thinking of changing the input speed sensors 1 and 2 on my ZF5HP24 transmission. I have looked through all the instructions manuals regarding the transmission but I can not find anything regarding these 2 speed sensors? where they are located. Does any one knows if I drop the oil pan if I can change them or I have to loosen the valve body as well?
Thanks,
Leif
Were you ever able to disconnect the electrical connector at the transmission and clean it? The fact that you have two codes that can be caused by electrical faults would prompt me to cover all those bases before I ever considered replacing a speed sensor. Regarding your measurments of the DC resistance of your speed sensor circuits, are you positive that the units were Megohms and not Kilohms?
I am attaching two documents. The first is a 5HP24 Diagnostic Guide with a flow chart that addresses P0715 - essentially it suggests confirming TCM connections and wiring. As you can see in the listings above from the DTC Summaries, P1797 can also be caused by a problem with the TCM connections or wiring to the ECM.
The second document is a parts catalog that shows how the speed sensors fit up into the valve body.
Hi Don,
I appreciate all the info.
Yes I have disconnected the transmission plug and cleaned it.
Also cleaned the TCM plug and TCM connectors.
Cleaned ECM as well.
Changed the TCM to a different TCM.
According to the trouble codes it suppose to be a limp home mode on both codes. However my engine quits and dies.
Yes I am pretty sure the resistance was 1300 K Ohms.
I have been a service electrician in my past and my meter is pretty good.
It was slowly building up to 1300 K Ohms. It was not instant.
I am at a stand still. The only thing I can think of is to change the sensors and or pull new wires from transmission plug to the TCM.
Thanks for the parts catalog, It seems that I can change the sensors if I drop the oil pan again according to the parts book.
The 2 sensors are about $50.00. On ebay.
What does it tell you that my engine dies instead of going to limp mode?
Wire problem most likely I think. But where?
Thanks,
Leif
I have to head out shortly so I'm just going to think out loud:
1. Have you followed up on Bob's suggestion that this problem could be related to the throttle body/throttle position sensor?
2. You have a 2001 transmission in this 2003 XJ8. Has the car exhibited this stalling ever since the transmission was changed, or did this behavior develop later?
3. Are you absolutely certain the fluid level in the transmission is correct? The fluid level must be set with the car as close to level as possible and with the transmission fluid between 30 degrees C and 40C. You can also check it at 50C, but this will represent the minimum fluid fill. If the temperature exceeds 50C the fluid level will be too low. You also have to move the gear shift lever to Drive and Reverse to ensure the valve passages are filled with fluid. See the TSB I am attaching.
4. P1797 indicates a problem in the CAN wiring between the TCM and ECM. With a basic ohmmeter you can test the Yellow and Green CAN wires for continuity, shorts to ground, and shorts to each other. See the schematic in the Electrical Guide, which you can download here:
5. The Turbine Speed Sensor connects directly to the TCM via Brown (color code N) and Green (G) wires. You check those wires for continuity, shorts to ground and shorts to each other also.
6. In thinking about the stalling happening at a gear shift, the ECM an TCM rely on the the engine load signal in order to manage smooth gear shifts. The primary signal for calculating engine load comes from the Mass Air Flow Sensor (MAFS). It's always worth cleaning the MAFS and its connector if you haven't already done so recently, but if your scanner can read live data, you can watch the MAFS output to see if it is varying within a plausible range. Typically it will read around 4-6 grams/second at idle and rise to 30 or more gm/sec at higher revs. If your scanner reads in pounds per minute look for 0.5 - 4.0+, and if it reads in pounds per hour look for 32-238+.
7. As always, mysterious behaviors like this can be the result of multiple components or systems operating out of spec, so think about the condition of tune-up items like plugs, filters, etc., and also clean the ground points referenced by the ECM and TCM if you haven't already.
Thanks,
Don,
I think it is time to have the throttle body rebuilt, like Bob suggested.
The engine has 130000 miles (208000 Km.) I had to rebuild the XK8 throttle body at 106000 miles. So I know it is time.
I will let you know if it takes care of my problem after it is done.
Thanks,
Leif