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Volkswagen Golf MK5 - ABS Sensor / Brake Pad Sensor Repair

Article Date: 26/08/16

Please note, the following article contains affiliate links. You don't have to purchase these products, although I appreciate it as it gives me a share of the revenue and helps me write more articles for this site and maintain it. They are links to the sellers I purchased the items from and the descriptions of the items I purchased to help you find them

One of the problems I encountered with my VW Golf MK5, has been with the brake pad sensor. When I was changing over the pads, I had a problem removing the old connector to plug in the new one for the brake pad wear. The connector attached to the car was corroded. This resulted in causing problems disconnecting the wires and eventually snapped off the connector. This results in a brake pad warning light being lit up on the car because the wire can't be connected.

I'm not 100% sure if they're tested for MOT's yet, but I wanted it fixed anyway due to the light nagging me. Fortunately this can be repaired and a lot of manufacturers are now making repair kits for these. There are two types of connector used for the Golfs one is an oval shape, another is an oval shape with a flat edge.

You will need to research your specific connector for my car these were the following (Oval with a Flat Edge), they're not used just for the brakes on the car. They're actually used all over the car as standard Male/Female connectors. The part numbers themselves, should be on the connectors for your brakes. If they're in poor condition just snip one off. You're going to replace it anyway.

Part numbers needed to carry out the brake sensor repair

Part Number Function eBay Link
1J0973802 (1J0 973 802) Wear Sensor Connector (Car) VW 2 Pin connector with 30cm tail leads 1J0973802
1J0973702 (1J0 973 702) Wear Sensor Connector (Pads) VW 2 Pin connector with 30cm tail leads 1J0973702
Both Connectors Same as above, but package contains connectors for both part numbers and the small components to assemble them. They don't come with any wires or finishing kits as they're meant to be used as "bare" terminals. So you can join the wires to new connectors yourself VW AUDI 2 PIN PLUGS 1J0 973 702 & 1J0 973 802

How to replace faulty brake pad warning sensors on a VW Golf MK5

Warning Light on Dash

This is generally what the Brake Pad warning sensor looks like when lit up on the dash. When I previously changed my brake pads, the connector broke, the light has been bugging me ever since and I meant to write an article.

As a note.... you can BYPASS the warning by simply joining the wires together. This should only be used as a temporary solution if you need to carry out the repair but don't have time (such as an urgent MOT).... but in any case, if the car fails an MOT because of this you have 10 days to fix it anyway so it's no excuse

I had some free time, so decided to do a write up on the process, so anyone with the same problems has a bit of guidance on repairing their brake pad warning sensors on their VW Golf MK5 or similar car

This is why it's always important to inspect/scan a car thoroughly as you don't know what hidden gremlins there are without having a look around yourself

Tools required to repair ABS sensor

These are the tools required to carry out the repair. Or at least the ones I used

  • Hammer
  • Flat Head Screwdriver
  • Metal Files
  • Wire Strippers
  • Pliers
  • Butane Soldering Iron & Solder
  • Metal Files
  • Repair Kits (1J0973802 and 1J0973702)
  • Car Jack
  • Insulation Tape
  • Heatshrink

It's a bit awkward, but there should be no reason you need to take off the discs / pads to fix the problem. Unless you have severely buggered your connector for your pads and the wire has snapped off at the pads themselves. In which case, I'd just buy new pads rather than the connector

Remove old connector chisel

The reason why the connector broke on my car is because the seating position where both connectors are lodged into was filled up with crap. It was rusted all of the rust had hardened up with junk and sealed around the old connector.

Before I did anything, I chiseled away at the old connector to remove it, from the slot. I wanted to tidy it up so the new connector wouldn't have this problem or run the risk of it

Busted and broken Another picture of the bad connectors as they had snapped off from the brake pad warning sensor
Old broken connectors

This is the brake connector from the car, as you can see it completely snapped off. So both repairs were needed. The wiring was in very poor condition.

Luckily the kit I purchased came with a large amount of wire to reattach it with, so it gave me room to play should I needed to cut the wires back

Repair needed A picture of the wires from the brake pad sensor. As you can see, the condition of these was bad too. Deteriorated and the connector had snapped off these. So both sides needed to be repaired
Repair kits for Golf MK5 brake pad sensors

This is a picture of the repair kits used on the vehicle, the ones I purchased came with everything pre-wired up to them. They also came with some heatshrink butt connectors to simplify the repair with some convoluted tubing as a finishing product.

They were well made and I had no problems fitting them. I purchased them from the supplier h2fconnectors2016 on eBay (UK supplier)

Filed down connector holder Before I carried out any repairs, I filed away any crap that built up inside the connector housing. Then used the new one to make sure it slid freely in and out of the place to hold it
Join the wires and test

I personally decided not to use the heatshrink butt connectors that came with the kit.

Firstly, I didn't like the idea of additional points in the circuit that could potentially cause the light to appear.

Secondly, I didn't want any bulk within the wiring, I wanted a clean look with the repair carried out. So decided I was going to solder the wires.

Once you decide what you're going to do, in my case soldering (or not). Strip back the insulation of the wires on both sides and twist them together. I also wasn't sure if it mattered which way around they went. So I basically went with RED > RED, and joined the other colour

I didn't actually use the soldering technique, because the iron I used was either faulty, or crap. If you're going to use it, make sure you get a decent model from somewhere online. I myself have a Weller BP650 EU which I purchased online from Machine Mart. I just didn't use it in this article

Secure your joins

Once you have tested to make sure the repair was successful each time and are happy to go ahead. Join the wires together, then use the heatshrink connectors over the top of the wires (or insulation tape) and heat them so it shrinks to size. This will prevent any shorting within the wiring and also help to protect it.

Plus it has the added benefit of making the job look more professional

Tidy up loom 1

This was the repaired connector on the car side of the wiring harness. The eagle eyed of you will spot the mistake I made when I wired this up, because I wasn't sure which was which.

For reference, the connector which is in this picture is actually the connector which should be attached to the brake pads. So when it comes to changing my pads and discs again, I will need to cut off this connector and reattach the other one in the correct manner.

For the purposes of this repair however, it worked. The car wasn't bothered and it will suffice for the MOT. After I had finished the repair, I wanted to make it as waterproof as possible. So prior to the repair I did the following.

  • Run two thin heatshrink tubes over wires
  • Run a 2 heatshrink tubes over tubing for ends

Once the repair was carried out, I used insultation tape all along the tube, to minimise the risk of moisture getting within and undoing all my work

One assembled

A picture of the repair, the connect has been attached from the first harness, and I had plugged it into the second plug for the brake pads. I temporarily joined the wires and again tested to make sure the warning light went out.

I then proceeded to heatshrink the wires again and tubing after I was happy everything was OK

Finishing up

Once everything was OK, I continued using heatshrink down the tube until the wires were covered for the brake pads too

Neat job finished

After the entire repair is finished, secure any wires. As I had decided to clean out the slot where the connector plugs into it does slide in and out easier now. This is also counter productive because it could potentially fall out

I fixed this by attaching cable ties to 3 different points on the loom. The connector is nice and secure now.

You can't see it from this angle, but there isn't actually much clearance between the Brake Pad Sensor and the caliper bolt. So being able to freely slide the connector out of the holder means it's held in place but easy to detach when replacement required

Warning Light Erased Success, the other warning lights on the dash go out when the engine is started. As you will see in this picture however the light has now disappeared so the repair carried out was successful.

Afterthoughts...

  1. ALWAYS, ALWAYS think ahead first - Heatshrink.... if you're going to use it. Think about what you need, put it on first!
  2. Make sure you get the connectors the right way around... It still works, means I have to fix it next time I change the pads
  3. Before you do any joins, twist the wires together. Keep going back and forth to the car and test the light is off/stays off