26 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHABS / PSM Lights - Brake Light Switch
Reported or suspected cause
"pedal position sensor"
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
Had the same issue on a BMW 325 and it was the "pedal position sensor" which is located on the brake master cyl on a BMW....for what it is worth....
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
the 1130 is most likey the maf sensor but you need to check the adaptaion values to be sure the 0446 could be related to that, ID CLEAR THAT ONE AFTER THE OTHER FAULTS ARE FIXED and see what happens
Leading evidence: '"pedal position sensor"' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is '"pedal position sensor"' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check adaptaion values' (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 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
Short version - ABS/PSM lights, cleaned MAF, lights went away.
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
It defiantly seems brake related as opposed to the MAF (which I have cleaned religiously).
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
Installed new MAF, cleared the CEL, but the ABS/PSM light remain.
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.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Check adaptaion values
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
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.
Suggestion
the 1130 is most likey the maf sensor but you need to check the adaptaion values to be sure the 0446 could be related to that, ID CLEAR THAT ONE AFTER THE OTHER FAULTS ARE FIXED and see what happens
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.
26 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
3 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
Another member had this issue and fixed the problem with a new brake light switch.
Good morning -
Yesterday when I was leaving my parking garage for work the ABS & PSM lights came on. Same thing on the way home. I did some searching last night and got a few helpful suggestions. After some testing in the garage this morning it seems that my brake lights are intermittently not coming on. I believe this is what is causing the fault lights to trip.
Another member had this issue and fixed the problem with a new brake light switch. Has anybody else changed their switch? Can somebody help with the part #?
Thanks,
Jeff
brake lighty switch is the switch on the brake pedal the the one with the air duct in the way of it,
it thould have a red end on it iirc
hold the brake pdeal down while instaling the new switch
It throws abs/psm faults becasue it needs to know if your on the brakes
Thanks again, Brad. I ordered the part from Sunset in Oregon today. It was $7.95 plus shipping.
Adam - I live in River North. Is your p-car a daily driver too?
Jeff
Jeff:
Yes, I do drive my car pretty much every day. I have a Jeep as well but much prefer to drive the Porsche.
Can you send me the part number or a link on the Sunset site? I want to order the same part.
Thanks,
Adam
I replaced the brake light switch today. The brake lights work perfectly, but the ABS / PSM lights are still coming on.
The lights illuminate when I RELEASE the brake pedal. Sometimes they come on when I release the brake immediately after starting the car and sometimes after I have been driving for a while.
Any ideas? It defiantly seems brake related as opposed to the MAF (which I have cleaned religiously).
Thank you very much for the offers to help! I am going to stop by Autozone to get the codes read and then report back.
I hope all of you have a very, very Merry Christmas!
Doug - I owe you a long overdue apology for dropping the ball on the seat cushions earlier this year. I was traveling A LOT for work and never had a chance to make it north. I sincerely appreciate the offer. How is the diagnostic software you bought working out?
Jeff
I ordered the Durametric cable and software early last week and it arrived today.
ABS Code:
Fault Number: 4340
Description: Stop-light switch
Repair Infomation: Check input signalsThere was also code:
DME Code:
Fault Number: P1574
Description: Factory Fault Code 364 - Stop light switch
Repair Infomation: Signal implausible
The lights were not on when I downloaded the codes. As I mentioned, they appear every time I drive the car the first or second time I step on the brakes after moving.
Any ideas? It seems like it still may be the switch that I replaced. It it possible that I got a bad one or broke it during installation? The brake lights work perfectly.
Jeff
I sure hope so.
The switch I replaced had a brown body and was mounted in a bracket facing the pedal. The switch gets pressed in when the pedal is released.
Is there another one I should be looking at?
Jeff
sounds right you replaced the one on the brake pedal and not the clutch pedal correct?
try pusing the brake and pulling the switch out all the way and letting the pedal adjust it
Well, I am in the same boat with a 2000 C2. Short version - ABS/PSM lights, cleaned MAF, lights went away. Few hundred miles later, ABS/PSM lights. Cleaned again, still the lights. Ordered new MAF. While waiting, but still driving car, got a CEL, P1128. Cleared that out, and the ABS/PSM light are still on, but no other fault codes.
Read a thread on this board, had the wife check the brake lights, and my center brake light works, but the corner brake lights don't. CEL came back on again. Same fault code P1128.
Installed new MAF, cleared the CEL, but the ABS/PSM light remain.
Waited til middle of the night, cranked up the car, drove all around my area, but did not use the brakes. No ABS/PSM lights. Various rpm ranges, up to 80 miles an hour, everything is cool.
Touch the brakes and as soon as you release the pedal, ABS/PSM lights up.
PSS9's to be installed next week. I am going to have those guys figure it out.
But, I did do the Ipod hack over this weekend. Now, I can't get the keys out of the radio. Gonna let the pros handle that one too.
1128 isnt brake related, its fuel mixture related most likey if you look at your adaptaion values you will find that they are negative incating a rich mixture.
at that point you check fuel pressure and its going to be ok, you will need a new maf sensor,
Brad -
Thanks again for following this thread and offering your insight. I drove to work this morning and ended up getting a CEL on the way.
I had the Durametric cable in the car so I got the codes before I shut the car off. As of this morning these are the codes:
moduleType = MotronicDME72
dtcCount = 3
Fault Number: P0446
Description: Factory Fault Code 95 - EVAP canister shutoff valve (function)
Fault Number: P1574
Description: Factory Fault Code 364 - Stop Light Switch
Repair Infomation: Signal Implausible
Fault Number: P1130
Description: Factory Fault Code 361 - Oxygen sensing adaptation, idle range, bank 2
9X6 ABS 5.7 Selected
Fault Number: 4340
Description: Stop-light switch
Repair Infomation: Check input signals
The EVAP and O-sensor codes are new as of this morning. I don't know if they are related or not.
Thanks again for the help.
Jeff
DME 7.8
9436 P1574 0-190 page 1
DME 7.8
p1574
0
Printed in Germany, 2000
0-190 P1574
364 Stop light switch - signal implausible
Diagnosis conditions
� Ignition on
Possible fault cause
♦ Stop light switch
♦ Wiring harness
The DME control module receives the signals from the stop light
switches via CAN bus.
Affected terminals
Diagnosis/troubleshooting
Note!
Work instruction Display OK If not OK
1 Check stop light switch ♦ Remove stop light switch
♦ Measure resistance between Pin
1 and Pin 4
0 - 5 Ω Replace stop light
switch
→ End
♦ Actuate stop light switch ∞ Ω
♦ Measure resistance between Pin
1 and Pin 2
∞ Ω
♦ Actuate stop light switch 0 - 5 Ω
♦ Install stop light switch ⇒ Step 2
2 Check wiring from PSM
control module to stop
light switch 1 for short circuit
to B+
♦ Remove PSM control module
connector
♦ Measure voltage between Pin 32
and ground
♦ Switch on the ignition
0 V Repair wiring harness
→ End
♦ Actuate brake Battery voltage
⇒ Step 3
DME 7.8 DME 7.8
0-190 page 2 9436 P1574
p1574
0
Printed in Germany, 2000
3 Check wiring from PSM
control module to stop
light switch 2 for short circuit
to B+
♦ Remove PSM control module
connector
♦ Measure voltage between Pin 37
and ground
♦ Switch on the ignition
Battery voltage Repair wiring harness
→ End
♦ Actuate brake 0 V
→ End
Work instruction Display OK If not OK
the 1130 is most likey the maf sensor but you need to check the adaptaion values to be sure the 0446 could be related to that, ID CLEAR THAT ONE AFTER THE OTHER FAULTS ARE FIXED and see what happens
It turns out the new switch was faulty after all. I bought a multimeter at Sears and took the measurements that Brad suggested. It turns out that there was a problem with the 1-2 pin connection. I took the switch apart and reassembled it carefully. Sure enough, after reassembly the readings were correct. A test drive confirmed that the problem is solved.
Thank you again for all of your help.
Jeff
This is a source reference. Confirm exact model applicability in the original material.
