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There isn’t power in the terminal that comes from pcm to the fuel pump relay at all so different relays won’t make a difference. Do you think a Body Control Module could prevent the PCM from sending power due to the BCM not sending the fuel enable signal?
That’* how I got the car to run by bypassing the relay. Runs perfectly when I have the fuel pump running the whole time.
I checked for power at the relay terminals in the fuse box and I only have voltage in the terminal that gets power from the fuse.
I should be getting two hot terminals right?
The other three terminals that have no voltage have continuity to the engine ground and battery ground so I’ll check the wiring for that tomorrow when I have time.
That’* how I got the car to run by bypassing the relay. Runs perfectly when I have the fuel pump running the whole time.
I checked for power at the relay terminals in the fuse box and I only have voltage in the terminal that gets power from the fuse. I should be getting two hot terminals right?
The other three terminals that have no voltage have continuity to the engine ground and battery ground so I’ll check the wiring for that tomorrow when I have time.
If the relay is working it will apply the B+ to the pump side. That is pin 87 I believe. The only way that pin 87 gets B+ is if the relay is working. The only way to check it is while cranking. KOEO will not work so I'm not sure you checked it right. Real quick to do is to swap the relay with another and see what you get. Do you have the wiring diagram of the circuit?
I tried swapping relays and nothing happens even after I get the car running with wires. My problem is that I don’t have power on the terminals that host pin 86 or 85 which is the energizing side of the relay. That’* what I meant when I asked if there should be two hot terminals. One for the energizing side and one for the open side in the relay. I get power on the terminal that hosts pin 87 but I need power on either pin 86 or 85 that way the PCM can do it’* job.
I insert wires into pin 87 and 30 to bypass the relay with a toggle switch to get the car running.
I’ll get that wiring diagram in a few minutes.
I tried swapping relays and nothing happens even after I get the car running with wires. My problem is that I don’t have power on the terminals that host pin 86 or 85 which is the energizing side of the relay. That’* what I meant when I asked if there should be two hot terminals. One for the energizing side and one for the open side in the relay. I get power on the terminal that hosts pin 87 but I need power on either pin 86 or 85 that way the PCM can do it’* job.
I insert wires into pin 87 and 30 to bypass the relay with a toggle switch to get the car running.
I’ll get that wiring diagram in a few minutes.
If you have B+ on pin 87 the pump will run. That can only happen if the relay is on and working. The relays only job is to apply B+ to pin 87 when the PCM grounds the relay magnet. That makes me think you have something wrong in your diagnosis.
Instead of pin numbers let’* go with this diagram so I’m not confusing you or myself lol
I really appreciate you helping me diagnosis this so thank you.
There is no power going to the relay magnet so a relay wont work either way. On the diagram it has for the fuel pump relay, it shows that the PCM should be sending power and that the magnet is grounded at all times.
I have power at M2 but I should be getting power at M1 when the key is just turned on and when the car is cranking but I dont. I have a good ground on K1 and K2 but I also see continuity from M1 to ground so I think I’ll check the connections next.
