Any Aston maintenance folks got any advice to share with me regarding this? I have already replaced both fuel pump driver modules but continue to get the fuel pump driver module off line code. I have the maintenance manuals/schematics for this car but it gets pretty involved tracing all the possible problems. Any advice would be greatly appreciated. Don

 

Do you have this in both pcm's or just 1 of them? What have you done so far??

 

Thanks for the reply......I don't know the answer to that question. I have replaced both FPD modules, that is all I have done at this point. I have been using just my hand held obd 2 tool. Don

 

So u haven't checked to see if the modules have power and ground, or if the pumps have a good 4 ohms showing there good? ...that would be a good start for u if this has not been verified..also it fault is with the signal feed back to the pcm, make sure this circuit is good and that the CAN network is not faulty/corrupt

this is way to in-depth, a dealer visit just might be cheaper than going the part replacing routine until you are sure of the actual concern..u have a P1233, this fault can be stored in the secondary or primary pcm, until u can figure this out..troubleshooting will be almost impossible unless it's a simply a blown fuse

 

I agree, this has just exceeded my diagnostic capability. The cars runs great. Is there any danger of being stranded by this malfunction?

 

The car runs? Ok this I didn't know, then if everything is up and running..sounds like it getting no ref signal back to the pcm, either sec or pri..this feed is a diagnostic wire that talks to the fpm, fpm talks to the pcm on this wire..believe it's pin 4 on the FPM..both are same pin cavity, pri fpm is a red/blu wire and sec fpm is a green/blu wire..if u know which pcm this would be easier, but first step after knowing which pcm would be to verify the diagnostic wire is good from the FPM to the PCM..in he case it gonna have to verify both PCM's

 

yes, I was aware that there was a communication loop from the FPM to the PCM but that was the extent of my knowledge. I read somewhere that swapping the leads between both FPM's might lead to a different dtc might help in diagnosing which side/FPM is the problem by giving a different dtc and that tells you what side/system is the problem. That is likely as far as I can go with my skill/diagnostic level. I know that my modules are good as they are new so it must be in the communication wiring. Don

 

By swapping the wire to the other module will not change the fault code..it would just be stored in the other PCM, it will not change the code, will still be P1233 that u originally had..only thing that might happen is the code gets cleared from messing around with that pin, the pin could be a loose contact and with messing around it makes a good contact in the other FPM..if u have no tools to get the pins out and do w drag test...u could always get some electrical connector grease and stuff each pin cavity, this will help make the pins have a good contact...also know at dielectric grease

 

I will try to locate the wires you referenced earlier and bend them around a bit. I have some dielectric grease to put in there. What is a drag test? Just a friction fit test, I get it..........Don

 

Yes, normally you find the same module pin and test it into each connector pin..then drag it out..I'd its loose, replace or tighten it

 

thanks Irish.....I'll let you know what I find.........Don

 

Irish....I have identified the blu/red and blu/grn wires and gently fiddled with the terminals for a tighter contact, then I took my long needlenose pliers and gently twisted each spade pin on both FPM's to produce a better contact. Packed the connector with dielecteic grease. Cleared the code and then went for a drive and code came back within about 2 minutes. I need the tool to remove the wires from the connector to check the crimp. Can this tool be had easily or is it peculiar to AM? Don

 

Stick a fork in me.......I'm done.........I'm going to let the boyz in Lake Forest figure this one out. I learned a lot about these cars though......First, the brits write the best manuals I've seen BY FAR. Highly detailed and well written. Second, if and when ours cars get old enough for the wiring to get old, burnt, and brittle.....WE'RE GONNA BE SCREWED! I see the refitment of a new wire harness as being a monumental job. The wires on these cars are super skinny and the bundles are still huge. On the positive side, the fit, finish and quality of the individual parts is very good. Got that going for us. Good thing the car runs well, anyway.

 

Did you ever figure out what this was. I have the same code going off on my 2007 db9. Thanks.