Question for the auto sparkies

[Hairyone]

Gday,

My sons 1996 Hilux has something wrong with the tail lights????
While he has his foot on the brake and left hand indicator on, both brake lights flash.......... and....... left indicator and indicator light on the dash are very dim when used on their own? My first thought was a bad earth ( still could be I suppose).....but Ive since found out its only while the car is running, not with the ignition is off, which throws me off a bit?

Any ideas where to start?
The battery light is always on too and the alternator IS charging too if that is relative???


Any thoughts where to start looking would be greatly appreciated.

Cheers Hairy

[john253a]

Do you have led tail light?
How have you tested if the alt is working?
The light one could also be the wire in back broken or fallen off

As for checking earth how did you do that, I like to run a temp wire from battery

[Hairyone]

Gday,
1.No don't have led tail lights.
2.Multimeter on battery when running 14.1 volts and only 12.6 volts when not running and auto sparkie checked it for me a week ago.
3.I havent had a look yet as motor running and not running thing threw me a bit???? Ill pull the covers off tommorrow and have a look.
4. Havent checked earth yet, but good idea with the temp wire.......

If its a bad earth like I originally thought, why would the motor running make a difference?

Cheers

[Steveyb]

Have you got trailer plug harness and is it full off water/mud?

[danmcccc]

bad earth

[Hairyone]

Thanks fellas.....Ive got a few days off so Ill have a look.....starting with cleaning the trailer plug as suggested then light sockets for bad earths.

Thanks again
Hairy

[CraigT]

I found in mine that the bulb connectors were corroded so was earthing bad. A bit of wet & dry to clean them up and I also used some electrical grease and it came good.
Only problem was I had to do all lights as I couldn't track it down to the problematic globe.

Good Luck !!

[Hairyone]

Well......
I Disconected the trailer plug as it was a bit dodgy.....
Cleaned the light sockets and the plugs in the loom with contact cleaner, pluged it all back and hey presto.....no flashing brake lights!

BUT.....no tail lights either!! (indicators and brake lights work fine)
Checked the fuse and replaced it .......just blew again.
Disconected the tail lights and put another fuse in and it blew again.......took out the fuse and tested both sides of the curcuit.
One side shows earth and the other +.....now being the lights are disconected, doesnt that mean that there must be a dead short in the wire somewhere between the earthing side of the fuse and the tail light loom?

[snakesoup]

check the number plate light/ wiring mate, almost the exact same thing happened to me not so long ago on the work ute and that's what it was

[Hairyone]

cheers mate....i'll try that one in the morning

[martynvella]

Has he fitted a stereo head unit recently. The dash light wire tests as a ground when the lights are off. Ground the unit to a bolt.

[Hairyone]

Has he fitted a stereo head unit recently. The dash light wire tests as a ground when the lights are off. Ground the unit to a bolt.

Yes he has......Ill check that too.....Cheers mate

[Hairyone]

Thanks for all of your suggestion.......
But the winner was............The bloody stereo!
Disconected the stereo and no more problems....

Thanks again for all your suggestions....much appreciated.

Cheers

[06xtracab]

Stereo was gonna be my suggestion too. I had the same problem when I fitted a new HU to my 94 Lux.

Rang my auto leccy go to guy and the first thing he said was: "did you put a new radio in it?...." And sure enough. I'd stuffed up the wiring.

[DeadlyBeast]

The devil is in the details.
Always a good idea to state what has been changed/added and start with that when fault finding.
Marty showing his experience there