Jump to content

Handbrake warning light on 1980 Triumph Tr7 coupe Instrument Cluster

Recommended Posts

Was wondering if anyone could assist me in fault finding my inoperative Handbrake warning light.

Initially it came on when the handbrake was applied 50% of the time but now it doesn’t work at all.

I have removed the centre storage box and accessed the brake switch which appears to make contact with the handbrake when it is applied.

However when I check the wire to the switch there appears to be no voltage there at all.

I assume there should be, and when the handbrake is applied it forms the circuit and illuminates the light on the instrument panel.

I have tried to follow the cable (Black/white) back to the dashboard but it is beneath the carpet and I lose it, so I have no idea where it goes.

Any idea what to do next?



Link to post
Share on other sites

It may just be an earth switch, does the switch actually provide continuity through when operated?


Link to post
Share on other sites

If you haven't got a circuit diagram it is here - page 5:


As Stewart says, the switch just  provides an earth for the warning lamp.

It may be that the warning lamp in the instrument console may be blown or not making proper contact. If the other lamps are working there should be power to the bulb.  

Link to post
Share on other sites

Quick checks - If you meter on the black/white wire with ignition on you should see 12v more-or-less if the bulb is good and making contact. The meter resistance is much greater than the bulb resistance so there will be next-to-no volts drop and the bulb will not light.

Earthing the wire directly should light the bulb.

Edited by RobH
Link to post
Share on other sites
  • 1 month later...



I have finally changed the warning light bulb,  but it still does not work when the handbrake it applied.

(I managed to change a couple of the dash bulbs at the same time so it wasn't a waste of time)

Looking at the wiring diagram there should be a connection from black/purple to a black/white.

I have tried to trace back the black/purple from the handbrake switch but the wire seems to head towards the rear of the car beneath the carpet at the side of the transmission tunnel.

Can't find it anywhere in the back of the car.

Could it be threaded through the floor and running externally?

I will persevere,  as this is now the only snag left to rectify.







Link to post
Share on other sites

Wire runs back to behind the trim behind the seats and then runs across to the passenger side before running forward along the side of the footwell. I am not sure how it finally gets to the instrument cluster however.

See the attached photo which shows the wiring in this area.




Link to post
Share on other sites


Well I fixed it!

Removed centre storeage consol, & back panel to locate the wire, found it, followed it down the passenger side beneath the carpet and it came into a multi plug where it joins onto the black/white.

Nothing found there.

Had a look under the centre grill cover on top of the dashboard - loads of wires & plugs.

Pulled them all out one by one and found one end of a multi plug with a black/white & green/white.

Fiddled about & found the other end - put them back together and the light now comes on when handbrake is applied.

How on earth did they come apart?

A good job done as I managed to replace 3 dash bulbs and the clock I bought about 2 years ago, and never got round to fitting.

Thanks to those that offered the advice - much appreciated.






Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.