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Need Help with some codes

Old Aug 16, 2008 | 04:58 PM
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Default Need Help with some codes

My car recently picked up some problems while its running. It will drive just fine, then randomly stall and cut out.

Codes

P0122 Throttle Position Sensor Circuit Low Voltage
P0121 Throttle Position Sensor A Circuit Range/Performance
P1635 5 Volt Reference out of Tolerance

Battery Voltage is 12.03




Gray wire @ TPS is .01 V

Black wire @ TPS is .01V

The signal wire was .01 @ idle. It would pick up as I moved the blade.

The voltage @ the C8 pin (5V reference TPS) on ECM was 2.0V


I think my reference wire has a break in it somewhere between the pin and the pigtail. But I don't understand why the voltage coming out of the ECM is only 2.0V.

I swapped in a spare ECM I had to verify the voltage at the pin. It should be a good ECM. So I haven't checked the voltage from the ECM that I normally run in the car. But the voltages at the pigtail were the same for each computer I used.

Any suggestions on what I should do next?
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Old Aug 16, 2008 | 05:35 PM
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is this with the tps unplugged? .01v
.01v at the ground with it pluged in back probing the connector would mean the grd is open.
the refernce 5v is shared with map egr tps abs
i would unplug some things and recheck it.
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Old Aug 16, 2008 | 06:54 PM
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Yes this is with it unplugged.


With it plugged into the TPS, the gray wire is .02 V.
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Old Aug 16, 2008 | 07:36 PM
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I have continiuty between my ground and 5v reference which I'm pretty sure shouldnt be happening. I think I am going to pull the harness and send it off to speed scene wiring. It needs a couple other things fixed on it as well I think its a good time to send it off and get it all fixed.
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Old Aug 17, 2008 | 05:22 PM
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Originally Posted by Jordan S.
I have continiuty between my ground and 5v reference which I'm pretty sure shouldnt be happening. I think I am going to pull the harness and send it off to speed scene wiring. It needs a couple other things fixed on it as well I think its a good time to send it off and get it all fixed.
thats true but it can find a ground else where with out the harness being the problem. see the pdf. with something else wrong it will find a ground.
in any circuit where the voltage is the same before and after the load is no ground. voltage should always be zero past the load. now it could leak past the tps but where are the volts going ? i would take the egr map and the abs out of the equation to start.
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Old Aug 17, 2008 | 05:28 PM
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P01635 is the best place to start
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