ff33 xjs 2+2 1994 4.0
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From: miami
ff33 xjs 2+2 1994 4.0
Suggestions please. I am getting an ff33 dtc code which is checks ecm output to fuel injectors. I am getting good spark and have good fuel pressure. When I turn the key to the on position I get 12 volts to both fuel injectors pins. I have performed the dtc ff33 diagnostic procedure as per the jaguar aj6 diagnostic guide. The test resulted in all the wiring being good and them recommends a substitute ecm which I did with no change. What confuses me is that with the key on there is 12 v power to both pins, is that how it should be?
Also should there be a ground wire to the ecm case? I checked all the ecm power grounds and they are good and cleaned all grounding points in the engine bay as well.
Thanks, John
Also should there be a ground wire to the ecm case? I checked all the ecm power grounds and they are good and cleaned all grounding points in the engine bay as well.
Thanks, John
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From: France
The 12v to both pins (assuming the injector is attached to the connector) is because the loom is live from the 12v feed to the injector loom, through the injector and back as far as the ECU. Then the ECU activates the injector by earthing the loom to the ECU's earth pin.
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From: France
If you use a mechanic's stethescope, or a noid light, you can hear/see if the injectors are clicking.
The report back. Facelifts have all sorts of ways of not starting, lots on the forum to search for, and I know nothing about them. However it is worth checking that the relevant earth pin (or pins) in the multiplug connector to the ECU is making contact with the ECU pin and has continuity to the injector loom.
The report back. Facelifts have all sorts of ways of not starting, lots on the forum to search for, and I know nothing about them. However it is worth checking that the relevant earth pin (or pins) in the multiplug connector to the ECU is making contact with the ECU pin and has continuity to the injector loom.
Last edited by Greg in France; Today at 10:13 AM.
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From: Kent, UK
John,
You've mentioned the fault code but you haven't mentioned what are the symptoms of the car? Does it not start? Or is it starting but running badly? Or is it running fine?
I'm surprised at Jaguar's recommendation of changing the ecu, just based on a fault code. That seems really excessive and expensive. The ecus on 4 litres are not know problem areas. Corrosion on plug pins, possibly; but a failed ecu is unlikely. Don't change any more parts unless you're absolutely sure they are at fault.
If the car is starting and running, I would just clear the code, run the car normally and see when, or if, the code returns.
Cheers
Paul
You've mentioned the fault code but you haven't mentioned what are the symptoms of the car? Does it not start? Or is it starting but running badly? Or is it running fine?
I'm surprised at Jaguar's recommendation of changing the ecu, just based on a fault code. That seems really excessive and expensive. The ecus on 4 litres are not know problem areas. Corrosion on plug pins, possibly; but a failed ecu is unlikely. Don't change any more parts unless you're absolutely sure they are at fault.
If the car is starting and running, I would just clear the code, run the car normally and see when, or if, the code returns.
Cheers
Paul
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