PCM can't see any signal from the driver o2
10-11-2008, 09:38 PM
#1
PCM can't see any signal from the driver o2 Did a bunch of reading and am feeling pretty SOL about this.
Driver front o2 locked at 450mv and running open loop because of this. Passenger side o2 works fine.
Getting inactivity codes on bank 1
Tried different o2's so that's not it.
If the pink wire terminal D is the heater and the black wire is the ground then it's getting over 12 volts across that.
Of the remaining to terminals I get almost 3 volts on one and over 12 votls on the other.
I did ground those two terminals and the PCM registered like 17mv so that's a good thing I think.
I'm really out of ideas on why the PCM isn't seeing and o2 on one side other then wiring and I trying to figure out electrical issues in a wiring harness is like
Driver front o2 locked at 450mv and running open loop because of this. Passenger side o2 works fine.
Getting inactivity codes on bank 1
Tried different o2's so that's not it.
If the pink wire terminal D is the heater and the black wire is the ground then it's getting over 12 volts across that.
Of the remaining to terminals I get almost 3 volts on one and over 12 votls on the other.
I did ground those two terminals and the PCM registered like 17mv so that's a good thing I think.
I'm really out of ideas on why the PCM isn't seeing and o2 on one side other then wiring and I trying to figure out electrical issues in a wiring harness is like
Last edited by Aaron91RS; 10-11-2008 at 10:18 PM.
10-11-2008, 11:53 PM
#2
Pull connector off of pcm.
Check continuity between pcm connector and o2 connector.
Your voltages look about right for the high and low signal, as well as the heater. But, I wouldn't trust the ground so much by checking it from pin to pin. Check the ground on the o2 connector between the connector and the chassis.
Really sounds like a insufficient ground.
EDIT: Also, check for voltage between the ground pin on the connector and the chassis. If you see voltage, you definately have a bad ground.
Check continuity between pcm connector and o2 connector.
Your voltages look about right for the high and low signal, as well as the heater. But, I wouldn't trust the ground so much by checking it from pin to pin. Check the ground on the o2 connector between the connector and the chassis.
Really sounds like a insufficient ground.
EDIT: Also, check for voltage between the ground pin on the connector and the chassis. If you see voltage, you definately have a bad ground.
Last edited by Dan Stewart; 10-12-2008 at 02:16 AM.
10-12-2008, 01:26 PM
#3
When looking at the o2 plug with the snap part on top, the top right pin that says 'ped' would not get continuity when grounded.
I went back to the autoparts store and tested another one right there in the store and it worked.
Now keep in mind this is the 4th o2 sensor I tried.
First one was a stock length one that was in there when I got the car. Probably factory.
Next 3 were the 13111 vette o2's. Of those it took until the 3rd until I got a good one.
That's scarey the failure rate is so high.
Definitly something for other people to check if their o2's aren't working.
I went back to the autoparts store and tested another one right there in the store and it worked.
Now keep in mind this is the 4th o2 sensor I tried.
First one was a stock length one that was in there when I got the car. Probably factory.
Next 3 were the 13111 vette o2's. Of those it took until the 3rd until I got a good one.
That's scarey the failure rate is so high.
Definitly something for other people to check if their o2's aren't working.
