15 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHWeird ABS fault. Any thoughts?
Reported or suspected cause
aftermarket centre led brake light
Reported cause
No successful repair reported for this finding.
1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report identifying a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported cause
Another cause for our problem was an aftermarket centre LED brake light which needed a resistor fitting in parallel to make it draw more current.
Leading evidence: 'aftermarket centre led brake light' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'aftermarket centre led brake light' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check connections' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report identifying a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
I've cleaned the Maf sensor, checked all connections to speed sensors, replaced the brake switch.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
Checked the sensors as per Alex's guidance - no issues.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
I've cleaned the Maf sensor, checked all connections to speed sensors, replaced the brake switch.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
They cost around £100 per side, it is a repair cable with bare ends, so dead easy repair, you join it to the old one under the trim panel by the battery.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
15 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
1 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
I cleaned them up and this worked for a while, but came back eventually.
2000 996 C2 6M Aero. Been chasing an intermittent ABS fault for a while now. Tried replacing the brake switch with a cheap one from Design 911 just to test. This made the problem worse as the ABS PSM lights came on the instant I pushed the brake pedal; rather than the usual 5-10 minutes of driving first. Took that out and put the old one back in and drove for 10 miles with no ABS warning! But next day the fault gradually returned. So I took it out and dismantled it (full of greasy gunk) reassembled and fitted and all was good again. Accept the problem gradually returned again. Any thoughts? P.S. The 'OE Match' one from D911 was very cheap and nasty.
Could be a number of things causing it: ABS sensor (x4) ABS reluctor ring (x4), MAF, brake switch, worn shocks (x4), the list is endless.
Are there any specific symptoms, eg: comes on when going round a bend or braking?
Sometimes it will come on as soon as I start the car (stays on) other times comes on after a mile or so. I've tried various things to see what triggers it i.e braking, reversing, swithcing off PSM, steering through tight bends, lights on or off, handbrake on or off when parked, driving in the wet; and there is no correlation between any of those things and the light coming on (along with PSM abviously). I've cleaned the Maf sensor, checked all connections to speed sensors, replaced the brake switch. Plugged my very basic fault reader in and it doesn't see any faults listed. There is no pattern to it triggering e.g. sometimes it will come on before I've even moved the car and other times not at all.
try taking a reading off each ABS sensor and make sure they are correct.
Have a read of this:
Self diagnosis and fix for ABS/PSM lights on
This topic comes up quite regularly, especially now these cars are knocking on a bit so thought I'd do a little write-up that may help folk. My ABS/PSM lights both came on last week so I had a go at fixing the problem myself. First thing I checked was the brake light switch. Easy enough to...
911uk.com
I had that ABS/PSM warning light thing for a while and I never got to the bottom of it. I think it was volts related as when I used the car regularly or kept it on a trickle charge, no problem. The first year or so when I got the car was very frustrating. Good luck
I also had an intermittent ABS light. Checked the sensors as per Alex's guidance - no issues. Turned out to be a rear reluctor ring. If you get the wheel off there is a window where you can inspect. Mine have broken on one side. I cleaned them up and this worked for a while, but came back eventually. Bit of a pig of a job but I did at the same time I refreshed the suspension.
Thanks Graham. Hope you are well. Car has been fantastic and sailed straight through MOT with no advisories. Thankfully the ABS light stayed off that day. The only thing I've had to get done was an alternator refurb
We had ABS issues and, like you I tried an aftermarket brake pedal switch. Even though it looked and tested identical to the OEM one, it caused faults.
Another cause for our problem was an aftermarket centre LED brake light which needed a resistor fitting in parallel to make it draw more current.
Update: So got it plugged in to PWIS today and the following came up 1) Brake position sensor signal fault (ordered Porsche one today) and 2) Steering angle sensor faulty. No live data being received. So it's a trip under the steering column to see what's going on
Also, for any members looking for PWIS equipped workshop in Essex; Daniel James Performance Cars in Rawreth. Had some interesting cars being worked on.
ABOUT US
The cable between the speed sensor the ecu often breaks inside the sheath.
This will give you an abs light and also psm, but depends if your car has PSM of course.
Mine used to take a few miles before it would lose connection, then started doing it quicker and quicker.
If you take the wheel off when you have started the car with no light on, you could wiggle the cable and see if it comes on, if it does you have found your issue.
Not sure if you would need to start moving a bit for the sensor to kick in actually.
They cost around £100 per side, it is a repair cable with bare ends, so dead easy repair, you join it to the old one under the trim panel by the battery.
Put "abs repair speed sensor" into design911 website to see part numbers.
Just saw your PSM light is on too, so reckon it is this.
I fitted the new Porsche branded brake switch today and abs warning is staying off. The new switch has a longer actuator than the old one. In between this I tried a cheapo one from Design 911 and that one made it worse! I disassembled it to compare to the original one and it was incredibly cheap and nasty quality. I thing Design911 'OE Match' is cheap crap. You get what you pay for. The other issue that Daniel James identified (steering Angle Sensor) led me to check it out. I felt around it and found it to be not fully seated. I compressed it and heard a couple of clicks. We will see!
This is a source reference. Confirm exact model applicability in the original material.
