Jawhead2000

Any ideas what is the common problem with this code P023a?

jft69z

Intercooler pump relay circuit trouble. Helping someone with that as we speak..... I can post the schematics etc if you need them.

Jawhead2000

So are you replacing the relay or is it the wiring going to the relay. The relay is located above the pump right?

jft69z

He's troubleshooting it still. Does your pump run at all? Did you check the fuse? Yes, the relay is above the pump at the front lower right side, attached to the side of the black plastic shroud.

Jawhead2000

I have power at the relay plug but no power at pump plug. Changer relay and nothing. Pump works if I run 12v +&- to it.

Relay doesn't click iether so I'm guessing no trigger.

jft69z

You should have power in 2 spots on the relay. Pins 30 & 85 (red/black wires). The trigger is the pink wire on pin 86 of relay. It's actually a ground that comes from the ECM to complete relay coil circuit.

You could ground pin 86 (pink) to see if relay pulls in & activates pump. If it does, it would indicate bad /open wire between ECM and relay harness pin 86, possible bad ECM ground, or maybe bad ECM.

What did you use as a replacement relay to test? An exact match, or something you pulled from another socket.

Did you follow the troubleshooting steps to check for high resistance, etc?

Jawhead2000

I purchased a relay that matches and bench tested them both against each other and have the same ohm readings. I also manualy tripped the latch on the bench to check to make sure they both latch. Along with checking all other fuses in car under hood and floor board they all are good. . Both red with black strip wires have power and light test light up. When I try tripping the relay with ground on the small "86" pin. I loose power to the 2 red wires "30 & 85" the power finally comes back after car sits for a few hours. Very weird. Any suggestions

jft69z

Call an 'Exorcist' your car is possessed

Shouldn't be losing any power there, it's basically hard wired to those terminals thru the fuse #32. Hmmmm

You don't have access to a real scan tool where you can cycle the ECM outputs for the I/C pump do you?

Jawhead2000

Yes I have a gmtech 2 and have cycled the pump relay circuit on and off but no click on relay and they toggle on/off and ok and not run. While it looses power I run scan and it changes to fault and notrun. When power comes back it reads ok and not run lol.

Jawhead2000

I figured the power was constant from fuse

jft69z

Try to cycle the pump with Tech 2, use ohmmeter to see if the signal is switching/grounding at the ECM (pin 86/pink wire). Just curious to see if the ECM is getting the message that it's supposed to do something, and this will also see if the output driver for that point is working. You may try both at the relay socket and backprobe the ECM connector itself if needed.

Jawhead2000

Where on the zr1 is the ECM connector/pink wire ?

jft69z

Looking at the schematic, it shows connector X3, pin 16 on the ECM.

SIK02SS

Any update to what you guys found? Mine flashed the P023a code yesterday after sitting outside all day and then turned off at lunch today after just scanning it

jft69z

Turns out it was one car, the OP was working on the car for someone else. I asked the owner what they found a couple of weeks later and he thinks it was either wires rubbing or water related. No real definitive answer unfortunately. Maybe one of those guys will have more info.

Jawhead2000

The problem was found. It turned out to be a faulty connection on the factory harness connector side of the relay. Replaced plug on harness and all was good.

SIK02SS

Thanks for the update and glad it turned out to be a simple enough solution

AdamD0509

Just threw this code today. Can you please help me out? Where is this plug located on the harness and what plug do I need?