Reverse switch not switching

Post by **CJH** » 11 Jun 2015, 20:28

I was working on my towbar electrics this evening, and realised that my reversing lights don't work. I can't say for sure that I've ever been aware of them working - I suppose I just assumed that they did.

I've traced the problem.

There's power to the switch on the gearbox, and when I short the terminals the reversing lights come on. So I assumed it was a faulty switch. But with the switch removed from the gearbox it works ok - if I push the plunger the switch closes and the lights come on.

So it looks like the switch isn't engaging when I put the gearbox into reverse.

So my question is, is there any obvious reason that the gearbox won't depress the switch plunger? Is there something missing from the gearbox? Have I perhaps got the wrong sort of switch? It looks like this one:

Post by **Oldiebut goodie** » 11 Jun 2015, 21:19

If you have a washer on the switch try it without it on. I had to try 3 different thicknesses of washer to get mine right. Mine was coming on when I changed gear not just reverse.

Post by **CJH** » 11 Jun 2015, 21:54

Oldiebut goodie wrote:If you have a washer on the switch try it without it on. I had to try 3 different thicknesses of washer to get mine right. Mine was coming on when I changed gear not just reverse.

Got it in one - thank you. I removed the 1.5mm washer, and now I've got reversing lights. I'll need an unwilling assistant to help me check that it's working as intended, i.e. not coming on in other situations, but at least I know how to sort it out now, thank you. It seems odd that it should be so sensitive to the washer thickness.

Post by **CJH** » 11 Jun 2015, 22:07

Actually I didn't need an unwilling helper - it's easy to test in the dark. It works perfectly without the washer. I know this switch is above the oil level, but I wonder if I should at least put a 'gasket paper washer' on it to make sure it doesn't leak.

Post by **Oldiebut goodie** » 11 Jun 2015, 22:38

I knew mine was coming on at other times as my ultrasonic reverse sensor gives a beep when powered up - I wouldn't have noticed it otherwise. I shouldn't think that you would need a gasket as there shouldn't be any pressure in the gearbox.

Club 80-90 Forums