Crikeymikey
A2OC Donor
SHORT VERSION
Faulty hazard relay. 8Z0 941 509 B. Fixed for £20 (used).
LONG VERSION
Hazards were going off intermittently earlier this year, without any obvious pattern of behaviour. Never whilst driving. Ambient temperatures did not seem to be a factor but I suspected a dry joint on a pcb somewhere to be villain of the peace, one way or another.
The problem would always cancel from the hazard button on the dash.
Diagnostics (I use an OBDelevenPro) suggested that there wasn't an external source (petrol cap, interior monitoring, boot lid, etc) causing the trigger. Additionally no fault codes were being logged.
Searching here on the forum I discovered this is a common problem, often leading to suggestions that the CCCU was the likely culprit but rarely was such speculation confirmed with a successful replacement and fix.
Fearing the worst, I decided to go down the easiest path and first replace the hazard switch (thanks @ICowie ). This made no difference and the hazards continued to go off randomly every few days. I did take the opportunity to clean a sticky cup holder so not a complete waste of time.
Next easiest to replace, I figured the hazard relay could be the cause. Thanks to @A2Steve for that item. I took this opportunity to do the Comfort Blinker mod.
It has been 4 weeks now and despite varying temperatures and conditions the hazards are behaving themselves.
So not a John Grisham worthy outcome, but a result none the less.
Thanks again to Iain and Steve, and thanks to you for reading this nonesense.
Faulty hazard relay. 8Z0 941 509 B. Fixed for £20 (used).
LONG VERSION
Hazards were going off intermittently earlier this year, without any obvious pattern of behaviour. Never whilst driving. Ambient temperatures did not seem to be a factor but I suspected a dry joint on a pcb somewhere to be villain of the peace, one way or another.
The problem would always cancel from the hazard button on the dash.
Diagnostics (I use an OBDelevenPro) suggested that there wasn't an external source (petrol cap, interior monitoring, boot lid, etc) causing the trigger. Additionally no fault codes were being logged.
Searching here on the forum I discovered this is a common problem, often leading to suggestions that the CCCU was the likely culprit but rarely was such speculation confirmed with a successful replacement and fix.
Fearing the worst, I decided to go down the easiest path and first replace the hazard switch (thanks @ICowie ). This made no difference and the hazards continued to go off randomly every few days. I did take the opportunity to clean a sticky cup holder so not a complete waste of time.
Next easiest to replace, I figured the hazard relay could be the cause. Thanks to @A2Steve for that item. I took this opportunity to do the Comfort Blinker mod.
It has been 4 weeks now and despite varying temperatures and conditions the hazards are behaving themselves.
So not a John Grisham worthy outcome, but a result none the less.
Thanks again to Iain and Steve, and thanks to you for reading this nonesense.
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