Warning...electrical diagnosis is not my forte. I have a 90 FJ62. Check engine light came on and diagnosed code 22 (water temp sensor) and code 11 (momentary interruption in power supply to ECU). Fixed/replaced the temp sensor. On to the ECU. Ran troubleshooting from FSM pages FI-30 to FI-32. I showed voltage in all circuits (step 1 of each). The M-REL to E1 was a little low but I suspect it may be my technique.
I am thinking of checking the ECU ground (the harness). Where is that located? Also where is the EFI main relay located so I can take a look at that ground as well? Anything else I should look at? Finally, is it OK to drive around with this issue? I don't want to get stuck somewhere. Thank you.
Edit: I located the EFI main relay. I should have checked FSM first...
Edit #2: My issue has morphed into something similar to Walrus and having issues with starting/idling. It will start and then whimper and die. Trying to add gas only hastens its dying out. Have checked most of the items suggested in this other thread. I have come to a point where the FSM has me doing the following...."check wiring between ECU terminal and body ground." Page FI-33, dealing with the FPR.
So, my same basic question...where does the ECU harness get grounded? Is it somehow tied into the chassis frame grounds? Appreciate any assistance.
I am thinking of checking the ECU ground (the harness). Where is that located? Also where is the EFI main relay located so I can take a look at that ground as well? Anything else I should look at? Finally, is it OK to drive around with this issue? I don't want to get stuck somewhere. Thank you.
Edit: I located the EFI main relay. I should have checked FSM first...
Edit #2: My issue has morphed into something similar to Walrus and having issues with starting/idling. It will start and then whimper and die. Trying to add gas only hastens its dying out. Have checked most of the items suggested in this other thread. I have come to a point where the FSM has me doing the following...."check wiring between ECU terminal and body ground." Page FI-33, dealing with the FPR.
So, my same basic question...where does the ECU harness get grounded? Is it somehow tied into the chassis frame grounds? Appreciate any assistance.
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