Non start - BCM? Damp wet weather

[kton200281]

Have done a search on here and seen a few similar posts but with no real answers other than it went away in dry weather.

 

Issue surfaced a month or two ago, a couple of the lights on the dash were lit very dim, and flashed when indicator was on. Then, next time I turned ignition on the ESP error appeared, and engine management light (as a result of the ESP I suspect). Car started fine, and then when turning off and back on, the ESP disappeared. This morning, same issue, hadn’t used the car for maybe 4/5 days, and when ignition turned on (before actually starting), ESP error and engine warning light. But this time, engine tuned kept turning over and didn’t start. Turned key off, back on, and this time it started.

I have heard that this could be down to damp / water getting into the BCM. It does seem to happen when it has rained, or been cold and then rained (thus causing damp). I am also not sure if it could be the battery, but it turns over quickly enough, whereas I have had a bad battery in the past and it turned over slowly. Unless of course there’s something else amiss with the battery. Car was driven 20 miles this morning, started up 3 / 4 times when I arrived at work, and no warnings or issues. Sounds definitely an electrical problem but any suggestions on where to start? A lot of the threads on the issues with damp seem to end with no real resolution other than people running the air con and opening the windows in the dry weather. But I can’t worry about this every winter especially as it didn’t want to start this morning and just turned over. Must be something to do with the electrics that control the fuel pump / ignition that didn’t want to allow it to start. Or immobiliser. I have no clue! 😊

[pikpilot]

Your conclusion about damp weather is probably correct from having had the same issues myself.

During these damp days, always have the air condioning ON if you have climatronics. This will reduce the humidy level in the car and it will be automatically controlled. Also helps if you select a higher than normal cabin temperature.

 

[kton200281]

Thanks for this - i am not sure though why it suddenly has appeared, i've had the car 9 x years and never had this problem in previous winters. The earthing points and cables under the battery do look old now, and the earth to the battery (mounting on body) has some slight green / white corrosion but its very minor. Usually its just the "ping" sound, esp warning, and then it starts up fine. Next time i turn off (even up the road 20 metres) and re-start, its gone. And wont return that day no matter how much i use the car. I saw posts about some BCM which sits behind the dash or something, and that water can get onto it, so keen to chase any leaks from the front of the engine bay / wiper area if thats happening and what's causing it. But not sure if this is the issue. Appreciate it is hard to track down intermittent things but there must be moisture entering something......