mamm7215

Alright, I've read the other threads about these low beam issues, here's mine to the letter:
No key in ignition-light switch on-no low beams.
No key in ignition-High beam switch on-High beams on.
Key on-daytime running lights on (low beam at 50%).
Key on-High beam switch on High beams on.
Fog lights do not work with High beams on. High beams off, fog lights work. Low beams never work, only dtr lights.
Single dual-filament bulb in each main headlight module.
I also get no Parking Brake indicator on the dash when I apply the parking brake (key on). I checked the Grey/blk wire attached to the ground sw. thingy when the brake gets pushed. Seems to work but I never did a continuity test to ground so maybe the circuit never gets grounded for the main low-beams to work...
My question...do you (anyone?) think it's more likely the..
1.) Parking brake not being grounded properly (I really haven't tested this well.)
2.) Multifunction switch
3.) Day time running light module (I'm in Canada.)
This is a little frustrating because while I can see OK with the high-beams at night, I'd like it to work properly.
Thanks...
M.

AlpineRAM

Does the dtrl go out when you apply the parking brake? (Key on lights off?)
With the fogs switch to on will they come on when you switch on the lights to low beam ?
With the switch in the position for low beams will the DTRL be on or will it just be dark?

Should help to isolate the problem

AlpineRAM

mamm7215

dtrl does NOT go out when I apply parking brake. (dey on lights off)
fogs switch on they DO come on when I switch lights to low beam
switch in the on postition-key on-dtrl on. key off-dtrl off.

Does this narrow things?

I may take a wire from the grey/bk park brake switch straight to neg bat terminal to make sure there's a ground.

Sidewinder

To test everything you could just disconnect the DRL module. If you do that you will NOT have DRL and your highbeam indicator light on your guages will not work but the lights SHOULD work as normal (NON-DRL) lights ON /OFF / LOW / HIGH. I had mine like that for about a year till I decided to buy a new module.

The module is located on the drivers side fender.

Oh yea this information is for a '95. A '99 may or may not be different.

AlpineRAM

I second the idea of removing the DTRL module and seeing what it does. Also the parking brake switch can be faulty, do you have the brake indicator light when you apply the parking brake? If yes the switch is OK and has good ground. AFAIK the DTRL is on the high beam filaments with 50% voltage.
There's a security relais in the PDC, maybe swap this with the horn relais to check this out.

HTH

AlpineRAM

mamm7215

OK, removed the DTRL module and got no DTR, obviously. High beams came on when activated but NO low beams. I get NO brake indicator light when I apply the brake. The switch itself is just a mechanism that contacts the e-brake pedal when deployed and breaks contact with it when off. It seems to be good and works properly with the drl's. Pedal pressed=no dtr, Pedal released=dtr. So if the DTRL module seems good and e-brake switch seems good, are we back to the multi-function switch? Seems odd that I don't get the e-brake dash light, though.

spots

Stupid question but have you checked the bulbs? Checked for voltage at the light sockets?

mamm7215

Of course not, that would have been way too easy.
I guess since it was happening on both sides I ruled it out but I'm about to
go do that next. Thanks.
M

mamm7215

Curiouser and curiouser....
OK, I unplugged the left front headlight and with the headlamp switch ON I measured 12V from ground to each of the connections inside the switch. Then I switched on high beam and from the purple wire, I got 12V from contact to gnd and 0v to gnd on the other 2. The middle wire to the connector is the violet/white. I forget what color the 3rd one was. I may try 2 new headlights and then probably get another multifunction switch.

mamm7215

is there a difference between the 9007 headlamp and the 9004 headlamp?

AlpineRAM

Hmm- I don't understand this now-
dtrl does NOT go out when I apply parking brake. (dey on lights off)
fogs switch on they DO come on when I switch lights to low beam
switch in the on postition-key on-dtrl on. key off-dtrl off.
In one post
and another:
Pedal pressed=no dtr, Pedal released=dtr.



New bulbs would be ok, have you checked the relais in the pdc?
AlpineRAM

spots

Use a test light not a DVOM for testing voltage. DVOM will draw no amps. You can have resistance (no or low amps) but have 12 volts.

mamm7215

Sorry, AlpineRAM, typo on my part. E-brake pedal turns OFF dtr when pressed.
Seems fine. What it seems like is I'm not getting the voltage on the Violet/white
wire at the bulb, which is the low-beam power through the multi-function switch. Everything else seems to be in order. Bulbs OK.

mamm7215

OK, using a test light, with my headlight switch on, I get 12v light on all 3 contacts in the headlight connector. High beams on I get only 12V on the Violet/white wire. DTR on I get 12V on all contacts as well (or at least the light comes on, could be less voltage). Sound like a short?

AlpineRAM

Hmm- sounds like a relais problem to me- or the light switch, but wouldn't suppose so since the fogs work.
I don't think it's the multifunction switch since the fogs indicate that the truck knows you want low beam. I'd say relais or DTRL....Maybe you can ask a nice neighbour with the same year truck to lend you his module. (Low beam is a ground switched circuit AFAIK, you should get ground on the ground wire with light on- maybe check the ground connector on the light switch)


Puzzled
AlpineRAM