Engine check on permanently -no error code

[-Jc.]

Hi All,

The check light's been on for 10 years with no problems and no error code (it did fade in and out for a while, at first) and now that's an MOT fail!

So I finally decided to do something about it, so assuming that the ECU capacitors were behind it, I replaced them, plus a couple of resistors. No change. There was a fair bit of corrosion on the front of the board, which I've done my best to clean up. I've tested continuity of the pcb tracks where the damage was noticeable and they all check out fine.

The plot just got thicker when I tried a reset of the ECU by removing the 7.5A fuse -I noticed it was blown. Eagerly replaced it thinking that may have been the problem all along... no change.

So, the car runs fine, there are no error codes and it's been like this for years, BUT it will fail the MOT.

HELP! Any ideas? Anything else that I can test?

Cheers! -Jc.

[gymm]

Hi All,

The check light's been on for 10 years with no problems and no error code (it did fade in and out for a while, at first) and now that's an MOT fail!

So I finally decided to do something about it, so assuming that the ECU capacitors were behind it, I replaced them, plus a couple of resistors. No change. There was a fair bit of corrosion on the front of the board, which I've done my best to clean up. I've tested continuity of the pcb tracks where the damage was noticeable and they all check out fine.

The plot just got thicker when I tried a reset of the ECU by removing the 7.5A fuse -I noticed it was blown. Eagerly replaced it thinking that may have been the problem all along... no change.

So, the car runs fine, there are no error codes and it's been like this for years, BUT it will fail the MOT.

HELP! Any ideas? Anything else that I can test?

Cheers! -Jc.

Yes, it will fail. Mine offered a code last year which my mechanic identified. I imported the new part (some sensor) and he fitted it and it still triggered it. The old sensor was worn out so another was necessary. My mechanic satisfied himself that all was in order. He removed the bulb from the dash eventually. He told me that the exhaust bulb was already missing. When I bought it 10 yrs ago it had a 'boy racer' exhaust which the seller removed for me and replaced with the proper one. I think this was the reason it was removed. The Beat has always run fine. Hope this helps.

[stu g]

When I bought my latest Beat 4 years ago it had a problem of the error light coming on, but being weak/fady (rather than the light being fully on), and not having an error code. It was worse when it was rainy. Couldn't find the issue and went through the ECU and changed the capacitors, still no correction. I then took the exhaust off to de-rust and paint, and noticed that the connection to the lambda sensor was corroded. I cleaned it up and hey presto, no more error light. I think I can summise from this that either a poor connection or slight short was causing this. This is something you might look to check.

Stuei