Audi A3 ABS Wear Sensor Repair
Article Date: 25/02/2022
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Tools I used replace the Front Brakes on the Audi A3
ITEMS I PURCHASED FOR THIS JOB
This is the repair kit I used for my car. I've purchased these a few times from H2F Connectors on eBay. Each one is well built, and just works. They're also cheap around £7.99 each normally.
He sells both of the repair kits too, there's one for the OEM harness (part number is 1J0973802) ** This is the kit used for this article ** and the one from the brake pad wear sensor itself (1J0973702), you can buy both of them from him. I used both of these kits when I carried out the repair on my VW Golf MK5
How I changed the Front Brake Discs, Pads and Calipers on my Audi A3
Jack up the car first and put on Axle stands. No pictures for this, but it should be fairly obvious
- My factory bracket that normally holds the connector was out of alignment, I had to use a hammer to bend it down and straighten it. It's behind the brake hose in this picture
- With the bracket now straightened it allowed me to start repairing. I recommend leaving the connector unplugged whilst doing the repair to prevent stretched wires
- This is the factory harness (or what's left of it after the corrosion set in). I stripped the wires, but you can see they're badly damaged
- Strip the wires on the factory harness
- Strip the wires on the repair loom
- Twist the wires together and test first
- Just a reference to the repair kit and wiring it up. This doesn't really matter because it's just a circuit based on continuity (so you can actually twist the wires together), but if you want to match the factory wires.
- Pin 1 on factory wire is red wire (goes to blue wire on repair kit)
- Pin 2 on factory wire is green wire (goes to red wire on repair kit)
- Once the wires are joined and tested crimp (or twist and heatshrink) them together
- After you have carried out the repair, cover it in the convuluted tubing and plug into the storage location using the notches onto the connector. The connector should now be repaired.
- Turn on your ignition to test it, the warning light should go out
Providing your car has been repaired, you should receive no warning. If the warning appears, either something has become undone (unplugged from the connector, wires no longer joined) or there's a poor connection. In which case you may be unable to repair it, but at least rectify the error using the below steps that I carried out. This gives you time to properly repair or investigate it
ADDITIONAL NOTES AFTER JOB
The wires on my loom were too badly corroded to carry out the repair successfully. After I joined the wires, the car carried out another check but ended up tripping the alarm again. In order to remove the alarm, I twisted the wires together, added some heat shrink over the joined wires and then zip tied it to the loom harness itself. This will at least prevent the wires having any further corrosion and keep them waterproof. I need to purchase a new loom in order to have an effective repair due to poor quality wiring. I did this because I knew my car was coming up for an MOT and it gets rid of the fault code light for the test. I then just have to carry out the repair at a later date at my own convenience
