Brake pad warning light

Prodigy_1978 · 03-09-2009, 04:23 AM

Hi all.

I have recently been having trouble with my Brake pad warning light. The warning light has been on since I bought the car which was about 5 months ago. First of all I had the brakes checked and they were fine no problems with the pads, but what the mechanic did notice the sensor had been cut an boshed. New sensor replaced. But the light was still on. He recommended I have a mobile auto elec take a look a look as the sensors before buying a front sensor as these were expensive.

I couldn't get hold of the auto elec guy and have been umming anr arrring whether to buy a new front sensor and attempt to replace this myself. I left the key in the ignition mark 2 I think it is called and the light was off. Hoorah. Only to start the car and move 12 feet and the light to come on B*****s.

I decided to squirt some WD40 onto the callipers (I know dangerous move) as they were looking a bit iffy and I have noticed a few squeaks on the drivers side rear suspension. ( A separate thread but could this be greased?) Then while driving the light went off!!!

The light was off for about 20 minutes. I restarted the car up and continued with my journey and the light came back on

. I decided to turn the engine off and back on and bingo the light is off

Could this be a dirty/dodgy sensor. Am I better off replacing the front as well just for good measure?

Any advice would be greatly appreciated.

jragan · 03-09-2009, 09:40 AM

The sensors aren't that expensive, and they're also very easy to replace. There are two sensors, one in the front driver-side, and the other in the rear passenger-side.

imz4n · 03-09-2009, 09:47 AM

The Z has two sensors, one on the left front and one on the right rear. Either one would set off the light. You might want to check for corrosion at the connector in the finder well. The sensor is simply the ground, loose the ground and the light comes on. The sensors are 7-8 dollars. If all is as it should be, you may want to disconnect the neg terminal of the battery for 10 minutes and then reconnect. This amounts to a reset of the electronics. I have seen where disconnecting the battery will fix many stupid electronic issues. You will need to reset your radio stations though.

pbdm4k · 03-09-2009, 10:53 AM

Sensors are for people who don't look at their brakes...

To get rid of the brake sensor:
1.) Locate your brake sensor.
2.) Cut off the brake sensor.
3.) Notice there are two wires for your sensor and expose the copper wire a bit.
4.) Wrap the two wires together.
5.) Cover with electric tape.

Tada, no warning brake light. No sensor.

BUT MAKE SURE YOU CHECK YOUR BRAKES REGULARLY IF YOU DO THIS.

pvr · 03-09-2009, 11:43 AM

Confused about the last post. If you join the wires, you make the circuit and the light will go on. The sensor is actually a piece of plastic where the wires meet, and if the plastic wears, the wires make the contact and the light comes on.

pbdm4k · 03-09-2009, 12:10 PM

Wrooooong...
When the sensor trips, it breaks the connection, that's what causes the warning light to come on.

Keeping the wires connected keeps the light from coming on. It's odd, but that's how the sensor works.

jragan · 03-09-2009, 12:50 PM

Quote:

Originally Posted by pbdm4k

Sensors are for people who don't look at their brakes...

To get rid of the brake sensor:
1.) Locate your brake sensor.
2.) Cut off the brake sensor.
3.) Notice there are two wires for your sensor and expose the copper wire a bit.
4.) Wrap the two wires together.
5.) Cover with electric tape.

Tada, no warning brake light. No sensor.

BUT MAKE SURE YOU CHECK YOUR BRAKES REGULARLY IF YOU DO THIS.

Or to make sure you never have to worry about the sensor just pop them out of their mounts (before they're "worn" obviously) and zip-tie them up out of the way so the sensor can't get damaged

But as stated above "MAKE SURE YOU CHECK YOUR BRAKES REGULARLY IF YOU DO THIS"

Prodigy_1978 · 03-10-2009, 03:49 AM

Thanks for the feedback all,

After a down pour of rain the light has come back on???? strange.

IMZ4N, what do you mean by corrosion at the finder well, and where/how can I check for this?

If I was to disconnect the negative terminal would this wipe out my alarm?

Would I be better off off purchasing 2 new sensors and attempt a complete new fitting? As I am based in the UK I will have to source a UK supplier and hope they do not charge excessive amounts of money.

03-09-2009, 04:23 AM	#1
Prodigy_1978 Enlisted Member 13 Rep 42 Posts Drives: Z4 2.2 Join Date: Nov 2008 Location: Cardiff, Wales iTrader: (0)	Brake pad warning light Hi all. I have recently been having trouble with my Brake pad warning light. The warning light has been on since I bought the car which was about 5 months ago. First of all I had the brakes checked and they were fine no problems with the pads, but what the mechanic did notice the sensor had been cut an boshed. New sensor replaced. But the light was still on. He recommended I have a mobile auto elec take a look a look as the sensors before buying a front sensor as these were expensive. I couldn't get hold of the auto elec guy and have been umming anr arrring whether to buy a new front sensor and attempt to replace this myself. I left the key in the ignition mark 2 I think it is called and the light was off. Hoorah. Only to start the car and move 12 feet and the light to come on B*****s. I decided to squirt some WD40 onto the callipers (I know dangerous move) as they were looking a bit iffy and I have noticed a few squeaks on the drivers side rear suspension. ( A separate thread but could this be greased?) Then while driving the light went off!!! The light was off for about 20 minutes. I restarted the car up and continued with my journey and the light came back on. I decided to turn the engine off and back on and bingo the light is off Could this be a dirty/dodgy sensor. Am I better off replacing the front as well just for good measure? Any advice would be greatly appreciated.
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03-09-2009, 09:40 AM	#2
jragan Imola Lover 26 Rep 749 Posts Drives: 2007 Imola Red M Coupe Join Date: Jul 2008 Location: Fort Worth, Texas iTrader: (0)	The sensors aren't that expensive, and they're also very easy to replace. There are two sensors, one in the front driver-side, and the other in the rear passenger-side. __________________ His: RIP-"Ruby" *E86 ///M Coupe: Pics Track Pics Short Vids Long Vids Hers: 997-1 C4S*: Pics
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03-09-2009, 09:47 AM	#3
imz4n Captain 57 Rep 822 Posts Drives: 2006 3,0 si TITANIUM SIlVER Join Date: May 2007 Location: Orange County Ca. iTrader: (0)	The Z has two sensors, one on the left front and one on the right rear. Either one would set off the light. You might want to check for corrosion at the connector in the finder well. The sensor is simply the ground, loose the ground and the light comes on. The sensors are 7-8 dollars. If all is as it should be, you may want to disconnect the neg terminal of the battery for 10 minutes and then reconnect. This amounts to a reset of the electronics. I have seen where disconnecting the battery will fix many stupid electronic issues. You will need to reset your radio stations though. __________________ SoCal Z Enthusiast contact me to get on the list. Events for like minded people and when you talk about your Z, we will know what you are saying. https://www.facebook.com/groups/ZSCCACalifornia/
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03-09-2009, 10:53 AM	#4
pbdm4k Lieutenant Colonel 74 Rep 1,689 Posts Drives: 2010 335d Join Date: May 2007 Location: North of the Border iTrader: (3)	Sensors are for people who don't look at their brakes... To get rid of the brake sensor: 1.) Locate your brake sensor. 2.) Cut off the brake sensor. 3.) Notice there are two wires for your sensor and expose the copper wire a bit. 4.) Wrap the two wires together. 5.) Cover with electric tape. Tada, no warning brake light. No sensor. BUT MAKE SURE YOU CHECK YOUR BRAKES REGULARLY IF YOU DO THIS. __________________ 2010 BMW 335d "Ha! She wants the D." 2006 VW Jetta 2.5 Once upon a time... '03 VW GTI, '99 Audi A4 1.8TQ, '00 VW Jetta 1.85T, '09 BMW 335i xDrive, '04 BMW Z4 3.0i, '01 Audi TT 1.8T, '04 Volvo S80 2.5T
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03-09-2009, 11:43 AM	#5
pvr Private 17 Rep 95 Posts Drives: F85 X5M Join Date: Apr 2008 Location: UK iTrader: (0)	Confused about the last post. If you join the wires, you make the circuit and the light will go on. The sensor is actually a piece of plastic where the wires meet, and if the plastic wears, the wires make the contact and the light comes on.
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03-09-2009, 12:10 PM	#6
pbdm4k Lieutenant Colonel 74 Rep 1,689 Posts Drives: 2010 335d Join Date: May 2007 Location: North of the Border iTrader: (3)	Wrooooong... When the sensor trips, it breaks the connection, that's what causes the warning light to come on. Keeping the wires connected keeps the light from coming on. It's odd, but that's how the sensor works. __________________ 2010 BMW 335d "Ha! She wants the D." 2006 VW Jetta 2.5 Once upon a time... '03 VW GTI, '99 Audi A4 1.8TQ, '00 VW Jetta 1.85T, '09 BMW 335i xDrive, '04 BMW Z4 3.0i, '01 Audi TT 1.8T, '04 Volvo S80 2.5T
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03-10-2009, 03:49 AM	#8
Prodigy_1978 Enlisted Member 13 Rep 42 Posts Drives: Z4 2.2 Join Date: Nov 2008 Location: Cardiff, Wales iTrader: (0)	Thanks for the feedback all, After a down pour of rain the light has come back on???? strange. IMZ4N, what do you mean by corrosion at the finder well, and where/how can I check for this? If I was to disconnect the negative terminal would this wipe out my alarm? Would I be better off off purchasing 2 new sensors and attempt a complete new fitting? As I am based in the UK I will have to source a UK supplier and hope they do not charge excessive amounts of money.
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