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On my way to work this morning and I'm slow moving traffic. Suddenly all the lights come on and car goes into limp mode, can't get out of second gear. Weirdly the window wipers are running constantly and can't turn off, also the Speedo is not moving.

Waiting for the AA.

Wow! That’s not a nice thing to happen!
Possibly alternator failure and battery died?

Edit: forget that if the wipers are running.

Hope you get sorted ok

Thanks, the most confusing part is the window wipers won't turn off

AA said it's an electrical fault with the gearbox. Can't clear the fault.

Classical canbus related issue…

One system is causing this..its failure causes the canbus to go crazy..continuous wiper motion is a classical indicator.

Full diagnostic check required..

Could be a dsc/abs ECU failure or a wiring issue..amongst many ..

Often needs an auto electrician as these are tricky to troubleshoot..

Thanks B21

When the AA got there all the errors had cleared from the onboard computer and car was driving normally. However the engine light stayed on (with the errors above). He was not able to clear them.

So I decided to get the car home, drove home 44miles without any issues at all, engine light remains on though.

Time to get someone to look at it I guess.

RAYK47 wrote: ↑Wed Jan 24, 2024 11:21 am Thanks B21

When the AA got there all the errors had cleared from the onboard computer and car was driving normally. However the engine light stayed on (with the errors above). He was not able to clear them.

So I decided to get the car home, drove home 44miles without any issues at all, engine light remains on though.

Time to get someone to look at it I guess.

Yes these faults are the most challenging….they often are actually in one area but ‘throw’ faults elsewhere..as I said needs a decent auto electrician who knows canbus to probably successfully troubleshoot..otherwise you are into just swapping parts till it goes away..

Have you got a decent code reader ?

The search button is your friend! viewtopic.php?t=130029

B21 wrote: ↑Wed Jan 24, 2024 12:03 pm

RAYK47 wrote: ↑Wed Jan 24, 2024 11:21 am Thanks B21

When the AA got there all the errors had cleared from the onboard computer and car was driving normally. However the engine light stayed on (with the errors above). He was not able to clear them.

So I decided to get the car home, drove home 44miles without any issues at all, engine light remains on though.

Time to get someone to look at it I guess.

Yes these faults are the most challenging….they often are actually in one area but ‘throw’ faults elsewhere..as I said needs a decent auto electrician who knows canbus to probably successfully troubleshoot..otherwise you are into just swapping parts till it goes away..

Have you got a decent code reader ?

Hi B21, i dont have a decent code reader (i was thinking of getting the INSTA/P and D software on a laptop, is that considered decent?)

dumaurier7 wrote: ↑Wed Jan 24, 2024 12:10 pm The search button is your friend! viewtopic.php?t=130029

The error looks very similar but it all seemed to clear itself after about an hour switched off. All that remained was the engine management light and the errors i posted above.

Tip #1 - It's time to stop thinking about getting a code reader. Get one. Insta + laptop if you are full nerd (it's probably the best), something handheld if you are over 50 & don't know how to spell linux or vm.

Tip #2 - Check your battery. Properly. If this is a 10 year old car on it's original battery, all you might need is a new battery. These cars go absolutely mental with batteries in poor condition, and the laws of physics dictate that any battery 10 years old is absolutely shot.

Tip #3 - thank me later

Just a thought but have you checked the boot for any water ingress

RAYK47 wrote: ↑Wed Jan 24, 2024 12:12 pm

B21 wrote: ↑Wed Jan 24, 2024 12:03 pm

RAYK47 wrote: ↑Wed Jan 24, 2024 11:21 am Thanks B21

When the AA got there all the errors had cleared from the onboard computer and car was driving normally. However the engine light stayed on (with the errors above). He was not able to clear them.

So I decided to get the car home, drove home 44miles without any issues at all, engine light remains on though.

Time to get someone to look at it I guess.

Yes these faults are the most challenging….they often are actually in one area but ‘throw’ faults elsewhere..as I said needs a decent auto electrician who knows canbus to probably successfully troubleshoot..otherwise you are into just swapping parts till it goes away..

Have you got a decent code reader ?

Hi B21, i dont have a decent code reader (i was thinking of getting the INSTA/P and D software on a laptop, is that considered decent?)

ISTA on a laptop is very good if yiu can manage to install it/understand it/use it..

Bimmergeeks Protool goes almost the full distance of ISTA and more user friendly ..anything you learn from ISTA can help with Protool so they are not mutually exclusive.

I have both…

The big big advantage of Protool being Android based is that I keep a cheap android phone in the car so you can do roadside assessments and resets..saved my bacon when the water pump failed 500 miles from home..

So get both!

RAYK47 wrote: ↑Wed Jan 24, 2024 12:20 pm

dumaurier7 wrote: ↑Wed Jan 24, 2024 12:10 pm The search button is your friend! viewtopic.php?t=130029

The error looks very similar but it all seemed to clear itself after about an hour switched off. All that remained was the engine management light and the errors i posted above.

My car did the same but without the engine check light. After having a proper scan done with ISTA the cause of the issue was found to be the ABS/DSC module which would just stop communicating on the CAN bus network. As actual vehicle speed is broadcasted on the CAN by this module, this would have a negative impact on a number of other modules causing them to go into error as they require a speed input to do what they do, this is why the speedo goes to zero and the wipers turn on before all the other craziness starts.