Headlights staying on

Does your Mitsubishi L300 make a strange noise? Need wheel alignment specs?
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Rattlenbang
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Headlights staying on

Post by Rattlenbang »

Hey all, I've got a strange thing happening to my L300 these days. The headlights - both inners and one outer - are always drawing power. Not a lot but you can see the filaments glow even with the vehicle shut off. When you actually apply power to the lights one of the inners then doesn't illuminate. I was wondering about how the van was converted to daytime running lights when it was imported. Did they use a module or something, and if so where is it usually found?

It's also randomly not firing up the glow plug relay, not sure if that's related.

Ive recently discovered some rat damage and now I'm also wondering if the little bastard had buggered up my wiring. The big +12 V cable between the two batteries was gnawed as well as a shifter boot. Haven't seen anything else.
My new novel A Dark and Promised Land has just been released by Dundurn Press. "On the eve of war he is compelled to reclaim her love, setting himself against his people amid a conflict that will form a nation." http://www.darkpromisedland.com/
Rattlenbang
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Headlights staying on

Post by Rattlenbang »

So it seems that the headlight/glow plug issue are related. I reconnected my battery again this morning and the lights now work as they should as does the glow relay. This has me stumped as I don't seen any possible connection between the two circuits.
My new novel A Dark and Promised Land has just been released by Dundurn Press. "On the eve of war he is compelled to reclaim her love, setting himself against his people amid a conflict that will form a nation." http://www.darkpromisedland.com/
sk66
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Vehicle: '91 Delica L300
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Headlights staying on

Post by sk66 »

I can't say anything about the daylight running lamps as we don't have them (US). But the most probable issue I can think of is a common short to ground... a lot of the ground wiring is shared I believe.
Steven
1991 L300
Harrisburg, PA
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Growlerbearnz
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Headlights staying on

Post by Growlerbearnz »

That sounds like an earthing problem, like power from some circuit has no direct way to earth (broken or gnawed wire), so it's finding its way through the headlamp filaments and possibly the relay coils.

The inner high beams glowing, but then not coming on is odd. Are these the facelifted headlamps, with projector low beams and reflector high beams?

I'd be pulling the lamps out and checking their wires and earths, and maybe swapping the bulbs around to see if the failure follows the bulbs or stays in the fitting.

I'd also track down the DRL module, because they're usually installed in a hurry using scotch-lok wire connectors (which are evil). Check the wiring that runs above the engine, through the air filter compartment, under the floor and up into the dashboard, and also the relays and fuses (and wiring to them) on the right side of the dashboard.
Nothing says "poor workmanship" more than wrinkles in the duct tape.
Rattlenbang
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Headlights staying on

Post by Rattlenbang »

I found the ground leads to the head was loose. But given that the problem was intermittent only time will tell if that was the issue. Not sure if those have any relationship to the above circuits.
My new novel A Dark and Promised Land has just been released by Dundurn Press. "On the eve of war he is compelled to reclaim her love, setting himself against his people amid a conflict that will form a nation." http://www.darkpromisedland.com/
Rattlenbang
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Headlights staying on

Post by Rattlenbang »

Nope that's not it, but I did get more information - what's happening is the vehicle is staying in accessory mode even with the key off, so the driving lights stay on and the radio and temp gauges, as well as power to the wipers. If I disconnect the battery terminal, it all shuts off and stays off when I reattach the battery. It doesn't happen every time I start the van, just sometimes.
My new novel A Dark and Promised Land has just been released by Dundurn Press. "On the eve of war he is compelled to reclaim her love, setting himself against his people amid a conflict that will form a nation." http://www.darkpromisedland.com/
Rattlenbang
Posts: 647
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Location: Victoria

Headlights staying on

Post by Rattlenbang »

Well, at least the headlight issue has been solved - one burned out low beam and a rat's nest behind the passenger side headlight cluster. Wires all chewed up including the ground. Strange to get such bizarre symptoms. I measured only 3 volts on all the headlight wires with the wires connected, jumping to 12V with the wires disconnected from the lamps, hence the dim glow that sometimes did or did not turn off when I turned off the van. All totally irrespective of the headlight switch position. Only the high beams responded to the headlight switch. And both high and lows were lit up instead of just low beams with switch in low beam position.

Turns out the daytime running lamp "module" was just a relay to the low beams that was energized when the key was in the on position, and supplying a ground.

This kind of thing makes troubleshooting a headache.
My new novel A Dark and Promised Land has just been released by Dundurn Press. "On the eve of war he is compelled to reclaim her love, setting himself against his people amid a conflict that will form a nation." http://www.darkpromisedland.com/
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