Light problems - Cars & Trucks

If 3rd light working then brake switch is not the problem, so it is looking like a wiring problem near to the rear light cluster. Run a live feed to the brake lights to rule out a faulty bulb holder. Probably not a ground problem as tail lights work, but wouldn't hurt to check that out.

This may be caused by several problem's that must be trouble shot by someone. these are a few area's that may be a cause of your problem. A light shortage problem in the light fixture itself located under the light bulb's, or a battery problem, a alternator and voltage regulator problem, a light switch problem located under the light switch knob on the dashboard display area or a wiring shortage which run's from the front of the vehicle to the back of the vehicle in various location depending on the year, make and model of the motor vehicle.

Light bulb problem ... you The "brighter" light is actually burning the turn signal filament not the tail light filament.

Your problem could be Rust in rear lights causing bad earth or shorting in parking lights or rear lights as plug shorting so.....unplug rear lights from plug to rear lights inc No plate light, switch on if still blows unplug both parking lights ....then OK so problem in f/p/lights,,connect up Left hand side ,,,still ok then problem in R/H/Parking light ,,,but dont forget when finnished to put them all back, and numberplate light as well (they are the most troublesome light)
Have a goodday

Make sure the fuse for the diagnostic connector is ok, look in the owners manual for it's location, it may be listed with other items so read the fuse descriptions for each fuse carefully.

had a similar problem on a ford and that was the earths to the light set up
do the lights also dim on and off when the indicators are on if so this is definatly an earth problem
good luck

Problem caused by light assembly L or R grounding out when water seeps thru tail light housing gasket. Change light unit assy to solve problem.

hi steve my name is dalip i was reading your problem, i think you have only electrical earthing problem check all earthing. you have not written whether you have diesel or petrol version if petrol check distributor and wires attached to engine (1) engine & body-earth wire, (2) all earth wires like back-light, dashboard-meter, (3) AC relay wires (4) may be alternator, self earthing problem, my email [email protected]

If the problem is that the brake lights will not turn off, the problem is most likely the CHMSL relay. An easy check is to take the cover off the fuse block mounted on the driver's side fender well and swap the fog lamp relay with the CHMSL relay. If that fixes it, just get a new relay for the fog lamps and you're good to go. Note, my 2002 s10 does not have fog lamps, but it still had the relay populated in the fuse block.