Handbrake light flickering - How to cure it.

10 years 1 month ago - 9 years 1 month ago #204 by David Aiketgate
OK you are finding that sometimes your handbrake warning light will flicker on and off as you drive along.
Firstly this light doubles as a low brake fluid warning - so check that.
Secondly, if your rear callipers are seized so they won't adjust or your handbrake cable has stretched then the actual handbrake lever will feel floppy and the light will flicker or come on all the time.

Do NOT continue to tighten the cable as this will cause the rear brakes to bind. The cable should be adjusted until the little levers on the rear callipers are just still resting on the stops(or no more than 1-2mm clear).

However, sometimes even if your rear callipers are correctly adjusted, the cable is also tightened properly and your fluid level is fine, the light still flickers on.

In that case it can be down to wear on the light switch

I removed the handbrake gaiter and had a look at the switch. Now, whether it's because the button has worn down through wear against the metal handbrake, or it's just a poor bit of design, I don't know but the problem is obvious.
The button only protrudes a few mm, meaning that the handbrake has to be almost fully depressed to get the light off.

The answer, to me, was to lengthen the button somehow.(notice how I avoided any reference to ****s there?)

So this is what I did. First chock the wheels, as you will be disabling the handbrake, and you don't want to end up in somebody's garden.
I pulled the gaiter off the handbrake, it just clips in, front and back.
Then I removed the cubby box to expose the cables, and I screwed out the adjuster until I could pull the handbrake up to vertical and out of the way.
Now you can see the switch, it is held in with two small screws.
If you remove the ashtray and surround ,you can get at the screw heads with a stubby screwdriver. Remove the topmost screw, and then loosen the bottom screw.
Now you can rotate the switch until it is horizontal, by pushing the top of the bracket down. With the switch now horizontal, and the handbrake out of the way, you can carefully drill a 2mm hole directly into the switch button. It only needs to be about 5mm deep.( you will see that the handbrake connects with the button on one side, so the hole needs to be over to that side)
What you do now is find yourself a nice 3mm fine-threaded screw about 10mm long. Fit the screw into the hole and screw it down leaving it sitting 5-6mm proud. Now you have a switch button that sits well up.
Pull the switch back into position and refit the bracket screw. Tighten both screws and refit ashtray.
Refit gaiter and tighten up your handbrake adjuster until you're happy with the pulled/on position.
Refit cubby box.
You will see that now you don't have to have the handbrake adjusted up so tightly, and you will also find that from the off position it needs a positive pull to get the light to come on. Result!

As a plus point, Sheila tells me it's a little easier to pull the handbrake on and off, so Brownie points for me there, then. LOL

Oh and DON'T forget to unchock your wheels before you try to move the car. Not that I did that; oh no not me, never. How could you think that? :outtahere:

David
:shrug:
The following user(s) said Thank You: Bob

Please Log in to join the conversation.

3 years 3 months ago #171182 by Blow-in
I have this problem too - handbrake light flickering on going over bumps despite the cable adjustment being OK.

Before I try this fix David - is it still OK after all these years? And am I right in my interpretation that the fix is to lengthen the button by putting a self tapper in the top of the plunger?

I'll try to take some pics when I get round to doing it.

Richard

1.8i Mk2 Solar Red, 16 inch square spoke wheels, MGFMania hood with zip-in glass rear window, DRLs, Kmaps ECU, Pipercross panel air filter, MGOC Supersports back box & some cockpit bling

Please Log in to join the conversation.

3 years 3 months ago #171198 by David Aiketgate
:yesnod: :broon:

I also found that another issue is the internal spring becoming weak/breaking inside the switch.

David
:shrug:
The following user(s) said Thank You: Blow-in

Please Log in to join the conversation.

3 years 3 months ago - 3 years 3 months ago #171203 by Blow-in

David Aiketgate wrote: :yesnod: :broon:

I also found that another issue is the internal spring becoming weak/breaking inside the switch.


Yes, I suspect that a worn/weak spring is the issue here, providing insufficient force to keep the plunger in contact with the handbrake lever. Rimmers list the switches as EEP191 at £19.49 inclusive VAT + delivery so a new switch in probably the better longer term answer.

Richard

1.8i Mk2 Solar Red, 16 inch square spoke wheels, MGFMania hood with zip-in glass rear window, DRLs, Kmaps ECU, Pipercross panel air filter, MGOC Supersports back box & some cockpit bling

Please Log in to join the conversation.

3 years 3 months ago #171206 by Blow-in
So I took a look at my switch by loosening the handbrake gaiter which clips in fore & aft.



The above was taken from the left hand seat and the switch plunger was quite greasy and this was making it resist sliding in so that it was pushing up sufficiently on the handbrake lever that it wasn't staying in the completely down position. The plunger has to move about 3mm down before it extinguishes the handbrake warning light. With the lever released but not going completely down it only had to move a mm up for the light to come on. This indicated to me that there was plenty of life left in the spring.

Before trying David's trick which I could see would work, I cleaned the plunger with a blast of WD40 and some tissues then worked the mechanism for a few minutes. All of a sudden the handbrake lever was going completely down. While the light still comes on the moment you move the lever, the lever seemed more inclined to stay down and a road test over the same roads that gave me a problem earlier in the week didn't cause any unwanted lights so fingers crossed that it's sorted (and the WD won't dry sticky - I did remove most of it). Otherwise I'll use David's fix - I don't think now that a new switch would help.

Richard

1.8i Mk2 Solar Red, 16 inch square spoke wheels, MGFMania hood with zip-in glass rear window, DRLs, Kmaps ECU, Pipercross panel air filter, MGOC Supersports back box & some cockpit bling
Attachments:
The following user(s) said Thank You: David Aiketgate, graham1, Skidpan

Please Log in to join the conversation.

9 months 2 days ago #189677 by Fil6909
Hi, I have this problem on my newly acquired '99 - mgf. not got my hands dirty yet , but I'm assuming this procedure essentially 'packs' the switch further forward, therefore the on /off button is effectively lengthened and comes into contact quicker , sounds easy enough👍. ... fingers xd thanks

Please Log in to join the conversation.

7 months 3 weeks ago - 7 months 3 weeks ago #190182 by Skidpan
Richard, your procedure worked for me, so thank you, no more annoying flickering of the handbrake light while driving.
Attachments:

Please Log in to join the conversation.

Time to create page: 0.131 seconds
Powered by Kunena Forum