Stop Light not working

[Paul and Judson]

1972 Series III with Servo Assist. Changed stop light switch, checked fuses, stop light does not work when brakes are applied. The rear running lights DO work. Any ideas and suggestions on what else to check.

[LaneRover]

Is there a chance that you have the wrong switch? I have heard the Rovers wok backwards from American switches . . . ie American switches work when pressed British switches work when released (pressing the brakes releases the switch.)

I would say pull the switch out but leave it connected to the wiring and see if they work whether it is pressed or released.

[I Leak Oil]

Is it adjusted correctly? If you remove the switch and work it by hand do they work? It's a pretty simple circuit. If it's not the switch or its adjustment it's probably a wiring\ground issue. Try bypassing the switch by connecting the two wires to each other and see if they work.

[Paul and Judson]

Thank you for your good advise. I tried all your suggestions and stop light still do not work. Anyone have other ideas? If it is a wiring/ ground issue, how do I proceed?

[LaneRover]

Are you getting power to the switch?

If so then check the continuity between the switch and the lights.

If that is good then check the ground at the back.

[msggunny]

try rotating the fuse. mine would do similar stuff and it was from bad contact at the fuse.

[LaneRover]

I second what gunny typed

[ignotus]

Have you checked the bulbs?...............If you have a test light, have someone step on the brake pedal and then start testing for power. When I don't have anyone to help I just use a piece of wood or something to wedge the pedal down. Do you have power to the fuse, switch, rear of vehicle? Just follow it until you can't find power.

gene

[Les Parker]

Bypass the switch

Try bypassing the switch with a jumper cable (no need to press the brake pedal if you do this) If you do not have a jumper wire, try a straightened out paper clip (temporary measure !). Once you determine that you have power to the switch connection, test the remainer of the wires to the rear bulb holder/bulbs.

[Paul and Judson]

I tried wiggling the fuse. There was no change. There is power to the bulbs. I checked power to switch. There is no power. Do I need to follow wires behind dash to look for break?

[mearstrae]

You need to sort it out with a test light or meter. See if power comes to the fuse and then across and back out (power on both sides of fuse). See if power goes to the switch and back out (power on both sides when pedal is depressed). Then see if there is power to the bulb socket while the brake is held down (remove the builb and carefully poke at the contact in the socket). This should narrow down the problem. Hard to teach basic D.C. electrics on a forum, *sigh*.

'95 R.R.C. Lwb
'76 Series III Hybrid 109
'70 Rover 3500S

[I Leak Oil]

When troubleshooting DC power just think of it like a plumbing circuit. Out of the well (battery) throught the pipes (wires) to the device (toilet, sink etc) to the drain pipes (more wires) and back into the ground.
You have to have flow and pressure at each point in order for the system to work when it's switched on. Trace it unil you find the point at which it's lacking flow and pressure (volts and amps). Electricity is a little more complicated than this but not much.

[Opabob]

Good explanation for us novices. Getting a new stop light switch set right turned out to require some fine tuning for me.

Sent from my DROIDX using Tapatalk 2

[Paul and Judson]

Thanks for all of the advice. It gives me more confidence on what to do next. After work I will start checking.