Numerous Vehicle Errors

[Refurbished.]

Halfords include coding as part of fitting. Website shows £146

[Al1040]

Thanks sjw

[greencode]

I went with Kwik Fit in the end. Cost around £160 fitted and coded. However, there has beeb a few issues since…

1. When I drove off it the Vehicle Status for Start/Stop said the engine needed to be running - It was! So, I went back, he plugged in his computer, did something, and that seemed to stop.

2. I drove about 20 miles and everything was okay but then the errors started popping up again.

The battery read 12.6 about 3 days ago and it's now 12.17.

Perhaps it needs a good run to get it fully charged??

[Agreeable Slick]

You might want to do a diode test on the alternator. The problem could be that it is acting like a parasite and taking charge back out of the battery when stationary and engine is off.

A lot of modern cars have a period of time when things will remain energised before they "go to sleep", and so can give you false readings when taking measurements. To get the most accurate reading then you would want to leave the car for at least 20-30mins to allow everything to shut off then do some more investigation. I know when I have been cleaning mine I can hear various switches and circuits clicking off for the first 20mins or so after I have moved it to a more cleaning friendly position.

[Refurbished.]

Local VW dealer Insist a VW branded battery is used and want £255.
Surely this is straightforward if you have obd11?

[greencode]

You might want to do a diode test on the alternator. The problem could be that it is acting like a parasite and taking charge back out of the battery when stationary and engine is off.

A lot of modern cars have a period of time when things will remain energised before they "go to sleep", and so can give you false readings when taking measurements. To get the most accurate reading then you would want to leave the car for at least 20-30mins to allow everything to shut off then do some more investigation. I know when I have been cleaning mine I can hear various switches and circuits clicking off for the first 20mins or so after I have moved it to a more cleaning friendly position.

Thanks for replying. Is there any tutorial on how to do a diode test?

[Lordie]

Local VW dealer Insist a VW branded battery is used and want £255.
Surely this is straightforward if you have obd11?

A car manufacturer will say anything to try and sell you more. They insist you use their screen wash too

[rwleigh]

Surely this is straightforward if you have obd11?

Yes, very...

[greencode]

What’s a little odd is this... tested battery (21.07). Went for a 20 mile drive. Initially the start stop didn’t work until around 5 miles in. No errors until around 17 miles in and then the 6 usual ones that I mentioned in my first post.

[Agreeable Slick]

You might want to do a diode test on the alternator. The problem could be that it is acting like a parasite and taking charge back out of the battery when stationary and engine is off.

A lot of modern cars have a period of time when things will remain energised before they "go to sleep", and so can give you false readings when taking measurements. To get the most accurate reading then you would want to leave the car for at least 20-30mins to allow everything to shut off then do some more investigation. I know when I have been cleaning mine I can hear various switches and circuits clicking off for the first 20mins or so after I have moved it to a more cleaning friendly position.

Thanks for replying. Is there any tutorial on how to do a diode test?

This is a semi decent website, with some good alternative things to check all by using a multimeter.

https://axleaddict.com/auto-repair/Alternator-Problems-and-Automotive-Charging-System-Tests