C1234 gremlin

[Ponch 04]

2004 Bonneville SE with 220,000 miles

This issue started about mid December last year. My anti-lock light would light up after I drove through some wet slushy snow on the highway. Ran a code reader and it showed C1234 "Left Rear WSS Circuit Open or Shorted" and C1245 "Master Cylinder Sensor Pressure Always High". I cleared the codes and it was fine for about 2 weeks when the Anti-Lock light came back on (wet roads again). This time it displayed just the "C1234" code. I decided to replace the left rear hub outright with a new Timken since it was started to make a bearing-going-out humming noise. Car was fine for about a month and now this past Thursday morning the "Ant-Lock" light went off again. Same code (C1234). I checked the wiring harness and I cannot see any wear spots or breaks in the wiring or corrosion in the connectors.

Any ideas where else I should be looking?

[harofreak00]

Did you check the connector that connects the rear wheel speed harness to the main body harness. It's located near the EVAP system on the drivers rear. Large gray connector. Check for corrosion there.

[Ponch 04]

Crud, no I did not. Is it easy to see and get from underneath the car?

[harofreak00]

You'll need to jack up the car to get your head under there, but yes. Just follow the wiring from both rear wheels to the connector.

[Ponch 04]

Did you check the connector that connects the rear wheel speed harness to the main body harness. It's located near the EVAP system on the drivers rear. Large gray connector. Check for corrosion there.

*Blows dust off of thread* Well after almost a year of being free of having this code showing up, it started up again when the roads started getting wet and slushy.
I checked the connection point where the rear left hub harness connects to the main harness and didn't see anything out of the ordinary. Then I looked where the main harness threaded between the rear brake line, fuel line, and cross member and low and behold the convoluted tubing had worn completely in half and 2 wires (red one and brown one) had the outside insulation worn down to bare wires. With a little cleaning, electrical tape, some larger convoluted tubing, and a few cuss words, it now works again without setting off the ABS light.

[STAGE III]

Way to stick to it ! I am still fighting mine but will be getting it in a lift and doing just what you did ASAP. Thanks for sharing a potential trouble spot!