P38A autobox not getting throttle position signal

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ned_

Active Member
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129
Location
Ireland
hello to all. My 2001 diesel has an errorcode, see below

regardless of load, the value never changes from 29.7

upload_2021-4-1_22-12-36.png



So im trying to figure out why. I have been looking at the BECM pinouts, this is the connector that goes to the autobox (I think) but its not clear to me which wire
provides the Autobox ECU with the throttle position signal?

Any assistance appreciated, thank you for reading.

upload_2021-4-1_22-15-56.png
 
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upload_2021-4-1_23-9-11.png

I am not sure how to read the pinouts. I am not great with wiring.
upload_2021-4-1_22-45-43.png


Below is the 'Instruments' readout on the nanocom. I think this readout comes from the BECM ?
If that is the case, the BECM can see the throttle position.

upload_2021-4-1_22-56-56.png
 
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hello to all. My 2001 diesel has an errorcode, see below

regardless of load, the value never changes from 29.7

View attachment 234741


So im trying to figure out why. I have been looking at the BECM pinouts, this is the connector that goes to the autobox (I think) but its not clear to me which wire
provides the Autobox ECU with the throttle position signal?

Any assistance appreciated, thank you for reading.

View attachment 234742

I am guessing but I suspect it gets the throttle position from the BECM. If you go into the EDC module is there a reading anywhere of the throttle position? Does it change? I guess if the car accelerates then it must do!
 
Morning Grrrrrr )

Yes indeed the EDC ecu does get a signal, you can see the value change in the pic below.

Throttle voltage and throttle position

upload_2021-4-2_9-37-23.png


Which leads me to think I could tap that line if I ran out of ideas.

Speaking of ideas I actually have a compushift that I bought for the M57 swap, that would control the 4HP22, but that's a whole different can of worms.
 
Silly question, but what's the car doing/not doing?
Air temperature showing nearly minus 40 deg?
 
Hi Ratae, the Outside Air Temperature Sensor located by the engine radiator is out of action, I don't think there are any adverse effects from that.
 
Silly question, but what's the car doing/not doing?
Air temperature showing nearly minus 40 deg?

On EGR models one of the temperatures is preset to -40 as it uses the MAF readings instead.

Without reading through RAVE I suspect the throttle pot position is read in EDC, passed to BECM and then fed back out to autobox. Is the reading on any of the BECM modules? Either way, it doesn't seem to be making it as far as the autobox ECU. Now we're really missing Wammers. Martyuk would be able to work it out. @Datatek may well know how it works.
 
What happened to Wammers?

Yes I think you are right, I do know that the accelerator pedal (throttle position sensor) routes directly to the EDC ECU.

I will fire up the nanocom and see can I get a reading in the BECM anywhere.
Also I might message Marty.

I never managed to install rave, I tried several times on windows 7 and then on win10, never succeeded and its hobbling me. I wish I had wiring diagrams.
 
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