Brake pad sensor light and warning light
01-01-2023, 08:04 PM
#1
Drifting
Thread Starter
Brake pad sensor light and warning light
I’ve replaced all the sensors. Still get warning light.
ohmed them out all are good.
Checked brake fluid, it’s full, added a smidge just to be sure.
jumpered the fluid sensor connector to check that.
warning light still on.
could be a break somewhere, but that would be hard to find.
is there a way to find which corner is unhappy?
Tia!
ohmed them out all are good.
Checked brake fluid, it’s full, added a smidge just to be sure.
jumpered the fluid sensor connector to check that.
warning light still on.
could be a break somewhere, but that would be hard to find.
is there a way to find which corner is unhappy?
Tia!
01-02-2023, 05:05 AM
#2
I've never invested in a diagnostic tool for anything pre ODB-2, as they are too marque specific and too specialized. IMO take it to your local Porsche Indy and pay them to diagnose the issue.
I did this for a recent intermittent ABS light that I could not find any problem to explain - the shop's tool diagnosed front right, and when they dug it out, it broke apart and was going rusty internally, so I'd have never been able to find that.
To check each new sensor in situ is quite simple, but it's unlikely to be the problem.
Have you still got the old sensors? Take one (or all) and about six inches from the plug cut both wires. Throw away the sensor, but join together the wires from the plug. You now have a plug-with-no-sensor that will always read 'good'.
Either connect one at a time or all four and see if the light goes out.
Seems unlikely you have a bad new sensor however.
Last edited by orangecurry; 01-02-2023 at 05:23 AM.
01-02-2023, 12:52 PM
#3
RL Community Team
Rennlist Member
Rennlist Member
Hi Tia,
The sensor pigtail plug is exposed to a lot of moisture and road debris. I would clean out all the sensor plugs and sockets with spray electronic cleaner while inspecting the pigtails for corrosion, abrasion, or other damage.
I would reassemble each using a small amount of dielectric grease to inhibit corrosion. I suspect doing that may solve your problem. For a street-driven car, I feel brake pad sensors are only needed if one does not inspect their brakes every few years when the wheels are off for other reasons. My car is subject to state inspections and I look at the wheel ends occasionally so I cut the sensor pigtail wires soldered them together and mounted them neatly with tie wraps. Makes changing pads a bit easier and less expensive. One can reuse the spiders (squeal silencer clips) at pad changes discussed on this page:
https://993servicerepair.blogspot.co...es-rotors.html
Andy
The sensor pigtail plug is exposed to a lot of moisture and road debris. I would clean out all the sensor plugs and sockets with spray electronic cleaner while inspecting the pigtails for corrosion, abrasion, or other damage.
I would reassemble each using a small amount of dielectric grease to inhibit corrosion. I suspect doing that may solve your problem. For a street-driven car, I feel brake pad sensors are only needed if one does not inspect their brakes every few years when the wheels are off for other reasons. My car is subject to state inspections and I look at the wheel ends occasionally so I cut the sensor pigtail wires soldered them together and mounted them neatly with tie wraps. Makes changing pads a bit easier and less expensive. One can reuse the spiders (squeal silencer clips) at pad changes discussed on this page:
https://993servicerepair.blogspot.co...es-rotors.html
Andy
Last edited by pp000830; 01-02-2023 at 01:45 PM.
The following 2 users liked this post by pp000830:
orangecurry (01-02-2023),
rdad993 (01-07-2023)
01-03-2023, 03:30 PM
#4
Drifting
Thread Starter
Yes there are Porsche diagnostic tools, but not sure which would work on your car.
I've never invested in a diagnostic tool for anything pre ODB-2, as they are too marque specific and too specialized. IMO take it to your local Porsche Indy and pay them to diagnose the issue.
I did this for a recent intermittent ABS light that I could not find any problem to explain - the shop's tool diagnosed front right, and when they dug it out, it broke apart and was going rusty internally, so I'd have never been able to find that.
To check each new sensor in situ is quite simple, but it's unlikely to be the problem.
Have you still got the old sensors? Take one (or all) and about six inches from the plug cut both wires. Throw away the sensor, but join together the wires from the plug. You now have a plug-with-no-sensor that will always read 'good'.
Either connect one at a time or all four and see if the light goes out.
Seems unlikely you have a bad new sensor however.
I've never invested in a diagnostic tool for anything pre ODB-2, as they are too marque specific and too specialized. IMO take it to your local Porsche Indy and pay them to diagnose the issue.
I did this for a recent intermittent ABS light that I could not find any problem to explain - the shop's tool diagnosed front right, and when they dug it out, it broke apart and was going rusty internally, so I'd have never been able to find that.
To check each new sensor in situ is quite simple, but it's unlikely to be the problem.
Have you still got the old sensors? Take one (or all) and about six inches from the plug cut both wires. Throw away the sensor, but join together the wires from the plug. You now have a plug-with-no-sensor that will always read 'good'.
Either connect one at a time or all four and see if the light goes out.
Seems unlikely you have a bad new sensor however.
Remembered I have a UDT999 I used to debug an Alarm issue. Pulled it out -- no errors across the board. Tried the durametric I have as well -- no change. I'm going to have to look at the connectors the sensors plug into -- otherwise -- I'm not sure what the next steps will be.
Mike
01-07-2023, 05:24 PM
#5
Rennlist Member
Isn’t this the light that comes on with the handbrake?
the contact on the end of the hand brake comes off and can cause this. There’s threads on this.
the contact on the end of the hand brake comes off and can cause this. There’s threads on this.
