I just checked the voltage at the PEM connector and I didn't get a reading.
I did different combinations without using the green/orange and black/red

the fuse relay 74 is good. which then traces back to the CEM if I'm reading this right.

what am I missing?

thanks
Paul

 

I pulled the CEM and it needed a little cleaning but nothing terrible went through all the fuses and the only one with an issue was "F66 Audio system control module (ICM); audio system relay coil". which I'm not sure what it does since the radio works. I'll replace it anyways.

went into fuse box in engine compartment checked fuses 30 32 36 all good.

took apart ECM connector and reconnected those too.

I'm at a loss as to what the issue is

 

I pulled relay 15 and put power to 1 & 2 and it clicks so not the relay,

 

and as another step: I do have continuity for the fuel pump. I'm going to put the CEM back and see if I get power at the fuel pump control module. no if I could figure out how to test that. anyone have any thoughts? or can point me in the right direction?


and I figured at this point I would document it for future reference

 

update: fuel pump control module replaced for $10 from salvage yard and the car now starts!!! now on to the next code!

 

Well I gave up chasing the same codes. and brought it to a shop.

and evidently the 2 parts I bought to repair it were bad.
Mass Air Flow sensor and the Fuel Pressure regulator. I could have been another year chasing these down.

now of course when I need it the heater core is leaking...sigh

 

well drove the car back from the garage this morning, didn't even get a mile and the CEL was back on with a P0172 code! same code it went in with!

anyone want to buy a volvo! sigh

 

Fuel trims can be so painful. If it makes you feel any better, I was in the process of replacing fuel injectors while chasing the same code, and I found a piece of blue shop towel in the fuel rail. Codes dont tell you theres a piece of fabric in the fuel rail!