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Cranks no start, CEL goes off with dash lights, Fan on KOEO
Hello all,
I am new to this group, and Jaguar's I got some direction as far a where to post, I hope I am doing it correctly this time. I just learned the XJ6 is the X300
I just got this 1996 XJ6 from my uncle. It looks super nice. I can't get it running.
Car was supposedly driven and parked at the house. After sitting for a few weeks the battery was dead and he put a new battery in it. The car never started and it sat there a year. One day he decided to put another new battery in it and it still didn't start. The dash to him was normal and the car cranked but would not start.
I have the car now. Yeah
Here is what I have done.
I notice the CEL turns on when the key is in the on position. when the majority of the dash lights turn off s does the CEL. No codes
When the key is in the on position the cooling fans turn on and stay on until the key it turned off.
There is no Fuel pump prime,
When the engine cranks there ir no pulse to the injectors or the the coils. B+ is there
When i connect a scan tool i get only a list of 2 items in the live view. Engine RPM = 32 and absolute throttle position = 0% no change depressing the throttle or cranking.
Tachometer does not move while cranking, however it does move slightly key on engine off while dash does self test.
Checked the fuses I think are relevant, none blown.
Replaced (twice) CPS
Purchased used ECU with non matching numbers and then with identical numbers, no change in anything
The ECU with mashing numbers was supposedly out of a running car.
The ECU and the connectors on the right side kick panel look clean and with no corrosion that I can see
Replaced battery with new battery.
I have 1 key and FOB. New batteries in the FOB and programed. Locks and unlocks well.
I have looked through the treads and have not found anything that has helped yet. It may be there, I just have not been able to come across it.
PLEASE HELP!!!
I am at my limit and I am guessing it is something simple that I am missing.
In my ignorant opinion I think the CEL light going of while the key is on and the fan staying on are related (not based on anything but my feelings) and there is some unit, ECU or other module not receiving power or ground.
May have put the battery in backwards in its history
Positive post fwd , mark with arrow on tape
This will fry the CKPS , ask me how I know
The CKPS will read 1300 ohms basic resistance
The TPS will not get below 11 or 13 % abouts ( its an absolute value considering the IAV will be open somewhat )
Don't loose track of your original ECU
There are 2 relays used at all times for the ECU
The first 3 seconds charging the fuel lines ( different then priming the cylinder's ) comes from the ignition switch command to the ECU and the ECU provides a ground to close the fuel pump relay
All 5 fuse boxes have hot at all times fuses 1 - 9
fuse 10 , 12 , 14 , 16 require the king relay in the corner of the fuse box to close , requires key on
Which leaves the remaining fuses hot at all times
Coolant fan is a hot at all times even engine not running but key on
To test the king relays ( Left engine bay fuse box is first power to the ECU ) have key in on position without starting , remove the king relays and they will click in your fingers back to the open position , with the exception of the left engine bay fuse box ( car horn , swapping option )
May have put the battery in backwards in its history
Positive post fwd , mark with arrow on tape
This will fry the CKPS , ask me how I know
The CKPS will read 1300 ohms basic resistance
The TPS will not get below 11 or 13 % abouts ( its an absolute value considering the IAV will be open somewhat )
Don't loose track of your original ECU
There are 2 relays used at all times for the ECU
The first 3 seconds charging the fuel lines ( different then priming the cylinder's ) comes from the ignition switch command to the ECU and the ECU provides a ground to close the fuel pump relay
Let me Start by saying THANK YOU VERY MUCH for the information. Parker 7 you are the bomb for helping with this information.
I do not know if the battery was ever installed in reverse, however I do know that it has not been installed in reverse since I have had the car.
What an awesome image with the pinout on the red and black connectors. I tested the resistance and although not 1300 ohms I believe it is within range at 1237 ohms. I feel the sensor and the wiring to the ECU are good. The AC voltage out of the sensor seemed good to me before. Now I know the signal is t least getting to the ECU.
There is no signal to the fuel pump relay, and even before all this jumping the relay will send B+ to the fuel pump.
I have the ECU's identified well. Good reminder.
Thanks again Parker 7
The diagram and information are great. I have been working and testing blindly. Knowledge is power.
#9 I tested before as it was obvious to see the operation. Input and outputs good.
#5 was new to me. What a great diagram showing the use of the relay. Relay did not function. Jumping terminals 30 and 87 made no difference in the function. B+ present at the terminals. Replaced with similar relay and still no function of the relay.
I noticed in the loom that there have been a family of mice living there at some point. I evicted them and looked for damaged wiring. I left the ignition on and while moving the wires I heard something activate in the engine compartment. Possibly the IAC not sure.
I cycled the ignition and the noise repeated and I noticed the CEL stayed on. I was excited.
Still cranks no start. and the tachometer read RPM's
All 5 fuse boxes have hot at all times fuses 1 - 9
fuse 10 , 12 , 14 , 16 require the king relay in the corner of the fuse box to close , requires key on
Which leaves the remaining fuses hot at all times
Coolant fan is a hot at all times even engine not running but key on
To test the king relays ( Left engine bay fuse box is first power to the ECU ) have key in on position without starting , remove the king relays and they will click in your fingers back to the open position , with the exception of the left engine bay fuse box ( car horn , swapping option )
Great Info on the operation of the power supply and the fan operation. I felt the 2 were related. Apparently not.
Doing some more digging I found chewed up wires in a loom, very hard to see how they ate it, since the loom looks to be intact.
I am leaving in the morning to Ecuador. I am happy about that, but I feel I am getting super close to starting the car and that makes me want to stay.
As a last effort while packing. I checked PW on the ignition coils, and I have it. Oh yeah. That is a new positive development.
Still no start and no fuel pump operation with everything connected.
Bypassed the fuel pump relay, Bypassed the #5 relay and the engine sounds like it hit a few cylinders.
Removed the plugs put some fuel in each cylinder and reassembled.
Started for a moment.
I now have to leave.
That is probably all I will be thinking about until I return.
This relay is controlled by the ECU and brings power back into the ECU along with fuel injectors and a few sensors
pic coming
You are the man.
I wish I wasn't going on this trip now. I want to solve it.
All the red B+ seems to be good from when I checked early on in the investigation. However worth checking again. No fuel pump relay control signal. Not sure on the #5 relay if the control signal is getting there.
You are the man.
I wish I wasn't going on this trip now. I want to solve it.
All the red B+ seems to be good from when I checked early on in the investigation. However worth checking again. No fuel pump relay control signal. Not sure on the #5 relay if the control signal is getting there.
Great reminder to avoid damaging an engine putting raw fuel in, I have seen individuals do that with a gallon container and a funnel. Not good. I probably shouldn't have worded it that way. I used a tiny tiny spray of carb cleaner in the cylinders. Still even like that it is not good to use much.
Right before I left I went again to the car, supplying fuel through he intake I could keep the engine running and revving well.
There is still no fuel pump activity due to the relay not being activated. and bypassing the relay activated the pump, still no fuel to the injectors.
I also see there is no injector pulse signal however B+ is present.
I tried to follow the 801S TITLE (jagrepair.com) link but since I am in Ecuador it will not take me to the site. I have had that happen to me on various sites. HomeDepot, Lowes, Arizona Courts, etc... When I get a VPN activated I will check out the link.
Sadly (as far as the Jag goes) I am in Ecuador until April. So I will be thinking about it until then.
There is an inertia / crash switch that will always be on the car's right fwd of the engine ECU , this will disable the fuel pump control by design
This switch can trip for no reason and can be pressed to reset ( doesn't always reset as can be fickle ) or you can jumper the 2 white wires on the 3 wire connector
Following will be a pic of a right hand steering model