Help!!! P1627

[jd daewoo]

My '00 lanos 1.6L has tripped a CEL code P1627. My fuel gauge hasn't worked in a while. When the code was tripped the radiator fans came on and the fuel gauge mysteriously started working, but slowly lowered to empty again (I have just under a half of tank of gas). I pulled the 6 pin fuel pump connector and tested the voltage. I read
Terminal 1=5.1V
Terminal 2=Ground
Terminal 3=0, but 12.2 volts for 2 secs when key is turned on
Terminal 4=Ground
Terminal 5=12.2V with key on
Terminal 6=0.9V, drops to 0 when keys is turned on then jumps back to 0.9V (in a second or less).

My question is about terminal 1 and 6. Is terminal 1 really supposed to be 5.2? Per the service manual on Inoperative fuel gauge the voltage should be 11-14. and What's the deal with terminal 6???

I'm assuming this is what's causing the CEL. Plz correct me if I'm wrong. I believe there is a TSB on faulty fuel level sensors.

Thanks.

[Daniel]

Terminal 6 is ground for fuel level sensor. You should read 0V all the time. Trace this wire for bad grounding.

Terminal 1 is power to fuel level sensor. On my engine management (red & white ECU connectors) it's fed by 12V but I've found another drawing where fuel gauge is powered by ECU hence maybe the 5V at pin 1. Your engine management may differ from mine.





All I've found about P1627 is

DIAGNOSTIC TROUBLE CODE (DTC) P1627
PCM/ECM A/D CONVERSION ERROR

Seems to be not related to fuel gauge but I may be wrong.

There were indeed TSB-004-01 & TSB-005-01 about incorrect fuel gauge readings.

Hope it helps,