2002 Cav ABS harness

The ABS light ( along with TC and Service lights came on intermittently a couple months ago whenever a large bump in the road was encountered, now on staedy.
I have traced the problem down to the left front sensor harness ( all others measure 5V at the connector with key tunred on, showing 0V at left front). Does this system use a short jumper wire ( 2 to 3 ft long) with coonectors at both ends from sensor to body harness, or use a long wire, with one conector at sensor and spliced into body harness? Called dealer and couldn't believe the price they want, but see some aftermarket harness that splice into body harness. Thanks
Jeff

There's a connector (12 pin or so) at the EBCM and one at the sensor. We always get the "patch" from the dealer that has the connector on one end and nothing on the other. I always thought they were pretty cheap. Be sure you're looking at just the two wires and the connector, not the whole harness. To replace it, I cut the original wires where it's easiest to get to them. Anywhere inboard from where they flex on the inside of the lower control arm is fine. The wires usually break where they bend at the steering knuckle, and can be repaired sometimes. Pull the harness apart and check if the copper is corroded already or not. If it's shiny, you can solder in a short section of wire and not spend the money on the whole harness. If it's already dull looking, keep cutting it closer and closer to the sensor connector. If you get to the connector and it's still dull, you need the whole section. Be sure you solder and heat shrink the wires, and keep them twisted as much as possible.

There is a Service Bulletin that applies to 2003-04 models, but it sounds relevant to your problem. This fixed my daughter's 2003 Cavalier.

#04-05-25-007: ABS Warning Light On, Traction Off Warning Light On, DTCs C1223 and C1225 Set (Replace Left Front ABS Wheel Speed Sensor Jumper
Harness) - (May 26, 2004)

Subject: ABS Warning Light On, Traction Off Warning Light On, DTCs C1223 and C1225 Set (Replace Left Front ABS Wheel Speed Sensor Jumper Harness)

Models: 2003-2004 Chevrolet Cavalier
2003-2004 Pontiac Sunfire

Condition
Some customers may comment that the ABS warning light and/or Traction Off warning light is illuminated. Upon investigation, the technician may find ABS codes (C1223 - C1225) set as intermittent or hard failures.

Cause
The cause of this condition may be the front wheel speed sensor jumper harness. The harness may check good with the voltmeter, but will not function correctly when subjected to suspension movement, vibration, and flexing.

Correction
Visually inspect the left front ABS wheel speed sensor harness connector. The wires may become unseated from the connector. This is especially important on the left side. If the wiring is faulty, replace the harness using the procedure listed below.
1. Raise and support the vehicle.
2. Unclip the 3 forward harness routing clips. These clips will be used on the new harness.
3. Remove the remaining 2 harness routing clips from the control arm. The new harness
includes these 2 clips for locating purposes.
4. Disconnect the wheel speed sensor connector.
5. Route the new harness into position and install clips.
6. On the old harness, cut the tape, pull back the conduit, and cut the wire harness to length.
7. Strip the wire ends, splice the wires using the provided splice clips. Put back in conduit and tape.
8. Lower the vehicle.

Parts Information
Parts are currently available from GMSPO.

Part Number Description
12187091 Wire, Wheel Speed Sensor


Here is an article on the subject from Motor Magazine:

ABS and/or "Traction Off" warning light on, codes stored.

The owner of a 2003-04 Chevy Cavalier or Pontiac Sunfire may come into your shop complaining that the ABS and/or "Traction Off warning light on the dash is illuminated. When he does, grab your scanner and start checking for DTCs. If you pull codes C1223 and C1225, chances are good the front wheel speed sensor jumper harness has an intermittent connection.

For some reason, the left-side harness seems to be affected much more so than the right, says GM. The car maker also warns that the connection may appear good in the shop when the harness is checked with a DVOM, because it's not subjected to the movement, vibration and flexing that occurs on the road. Visually inspecting the harness connector for wire pullout is a much more accurate diagnostic approach. If you find that the wires have indeed unseated from the connector, replace the jumper harness with a new, more durable design, Part No. 12187091.

To install the new harness, get the car on a lift and remove the three forward harness routing clips. These will be reused. Now remove the remaining two clips at the control arm and toss them (new ones are provided with the new harness). Next, disconnect the wheel speed sensor connector, plug in the new harness, route it properly and install the five clips.

Continue the repair by cutting the tape and pulling back on the conduit of the old harness. Using the new harness as a guide, cut the wires, strip the ends and splice the wires together using the splice clips provided with the updated harness. Push the conduit back over the new harness, then seal up the repair with electrical tape. To complete the fix, lower the vehicle and take to the road to ensure that the warning light(s) stays off.

Use your best judgment or consult a mechanic before attempting this. Good luck and I hope it helps.

The harness runs about $100 at the dealer, but there are several aftermarket ones available and on eBay for $30-$50. This part is the same for 1995-2005 models.

I don't mean to question you, but I really don't think the harness is $100. While I have not done one on a J Body, I have done them on numerous W and N bodies. It's so cheap that we don't even call the customer for approval before we do it if it's in for something that will fix, and we call if a hose clamp is leaking and needs to be replaced. I think the last one we got was about $12, and I know it was less than $20. Forgot exactly what he said it was. That's with a considerable commercial discount, but I doubt the dealer marks it up more than 5x what they charge us. It's 3' of wire and a connector, about $2 worth of materials.

J-Ri:
The reason i am asking is the local GM dealer quoted $193 Cad for the harness. I expected the jumper harness to have 2 connectors on it like my Trans sport van, but I couldn't find the body side of the harness, and you have confirmed it is hard wired into the harness, thank you.
Needless to say at that price I am going to explore other options, like splicing in a new section of wire where the flexing takes place. Almost 200 bucks for a weather pac connector, a bit of flexible wire and some weather shielding just can't be justified IMO..and the car has less than 50K kilometers, under 30K miles. Am I impressed??
Thanks
Jeff

That's going to be the best way to do it. I just looked it up on parts.com because, quite honestly, I didn't believe it was that much. MSRP was $110!

J-Ri:
Can yopu p[lease tell me where on the parts.com site you found the harness? found sensors, but not the harness itself. Interesting site tho, always looking for new parts sources especially for my U body van that GM is no longer supporting, thanks
Jeff

I just searched for the part number that's in the TSB that rdh2 posted, it came up with "this part has been superseded by P/N XXXXXXX", I clicked or searched that part, and it came right up. I have never bought anything from them, but I occasionally use it to search part numbers.

I have been fussing with this issue for the last several months. The dealer tried to tell me that it was going to cost $1800 to repair. I kid you not. They suggested I might want to think about investing in a new car. Really? Seriously? I walked out.

Came home, did some surfing, found the bulletin regarding this issue.

Had an oil change at a popular chain where they brought the lights to my attention (again). We agreed on the bulletin. Said they needed to order the harness from the dealer. Was quoted a price of $165. Definitely lower than the dealer's quote, but come on! They told me I could order the part myself online for less and bring it in and they would charge $85 in labor to install. Still haven't done it.

Not sure where to go from here. Not able to do the repair myself. Hoping to find a local mechanic who will listen and not order from the dealer. I have a feeling that if I order the part myself online and then take it to someone to install, no matter what, they are going to tell me that I have the wrong part.