2000 Safari RWD DLR not working

[kornphlake]

I have recently purchased a 2000 Astro with day time running lights, however the DRLs have ceased to illuminate during the daytime. I want the lights to work, I've checked the DRL fuse in the fuse box under the dash and the relay under the hood, both are in good condition. It appears the problem is with the DRL module, which I've been unable to locate and test. Can someone give me a clue where to look for the DRL module?

[mkj54]

http://www.chiltonlibrary.com/content/i ... 000202.pdf


I'm not sure if this link will work, but it appears what your looking for is built into the body control module.

I'm not sure about astros but some models of GMs don't have DRL come on until it's in gear. (i'm thinking cavalier for sure)

[kornphlake]

http://www.chiltonlibrary.com/content/images/WD/GM/000/WD_GM_000202.pdf


I'm not sure if this link will work, but it appears what your looking for is built into the body control module.

I'm not sure about astros but some models of GMs don't have DRL come on until it's in gear. (i'm thinking cavalier for sure)

I believe you're correct, the DRLs should only come on when the vehicle is in gear and the parking brake disengaged. Unless there is more than one switch connected to the BCM both are working properly as the lights on the dash to indicate the parking brake and gear are both working properly. My thought is that it is most likely the module, in the schematic you linked to there is a diode, I suppose the diode could have gone bad, does anybody know where this diode is located?

[Phantom]

Here is a diagram /pictorial type

http://www.gmpartsgiant.com/components/ ... 11006.html

Item #10

part #'s
12193602 RELAY DAYTIME RUNNING LP,(BLACK),(5-TERMINAL)(SPDT 280 MINI),(02.100) LM1 00-05 1
$20.52
$12.57
10 15306302 CONNECTOR HORN,(GRAY),(2-WAY FEMALE W/LEADS)(ROUND),(04.710) LM1 00-05 1
$31.22
$19.12
10 CONNECTOR RLY-DAYTIME RUNNING LP (NOT AVAILABLE) 00-05
10 CONNECTOR MDL-DAYTIME RUNNING LP CONT (NOT AVAILABLE)

[unrreal]

you may be overthinking this, i have seen on the s-10 blazers that whenever there is a short on the circuit it will fry one of the filaments in the light bulbs (they have two filaments) which is usually the one for the DRL'S. just my two cents...

[mkj54]

Unreal just might have it. DRL=high beams, does flash to pass work? Can you turn on the head lites and get high and low beams?

[RECox286]

My 01 DRL come on as soon as the engine is running irregardless of the gear selector. There is a little winkie in the center of the dash, (a photo cell, I recon) that runs the head lamps when it is dark , parking lamps during daylight. Other than that, beats me.

Bob

[kornphlake]

The headlights are the twin bulb setup with a separate bulb for the high and low beams, the high beam bulb is a single filament. I understand that the DRL module somehow pulses the connection to ground making the voltage appear to be less than a nominal 12v. I could be very wrong, after all that's what I learnt from the internets. High beams and low beams operate as expected when the ambient light sensor is covered or switched manually.

Reviewing the schematics, it looks like there's a DRL relay somewhere that is likely the culprit, the relay I checked is the generic headlamp relay. I'll have to poke around and see if I can find the DRL relay.

[toddb]

Maybe it is as simple as the emergency brake switch out of alignment?

[mkj54]

http://www.chiltonlibrary.com/ContentVi ... meset.aspx


Here are the three diagrams I can find. What I'm seeing is that the headlites always have power and they are controled on the ground side. The bulbs are good but it would help if we knew if flash to pass works. Also you might try dusting off the ambient lite sensor (maybe some compressed air in a can for computers) Then shine a lite in it and see what happens.

[kornphlake]

http://www.chiltonlibrary.com/ContentViewer/CVFrameset.aspx


Here are the three diagrams I can find. What I'm seeing is that the headlites always have power and they are controled on the ground side. The bulbs are good but it would help if we knew if flash to pass works. Also you might try dusting off the ambient lite sensor (maybe some compressed air in a can for computers) Then shine a lite in it and see what happens.

What do you mean by "flash to pass?" Turn signals? I've never heard this terminology before. As far as I can tell all headlamp functions are operating correctly except for the daytime running lights.

[Phantom]

I often see drivers "flash" their headlights to let other drivers on the road know that they intend to pass other vehicles ,to make other drivers aware of their intentions in hopes to avoid a collision .

[mkj54]

Your high beams come on when you push the turn signal wand away? Low beams are on when you pull it back? This is the only way I remember it working, try pulling turn signal wand towards you from the low beam position, should be spring loaded, brights should flash.

The key might need to be in the run position, the head lites may need to be on, not sure. Anyway look at the diagram in the first link. Flash to pass is built into the multi function switch, that's connected to the BCM, which grounds the DRL relay flashing the brites. The reason this is important is that if it works the DRL relay is good, and that diode is good, if not there is some more digging, hard to be sure yet. Back to the ambient lite sensor,if it's dusty or some how obstructed it could cause the BCM to sense it's dark, so I suggest shining a bright lite on it. It's just a photo resistor and it could have gone bad but we're still trying to narrow things down.

[kornphlake]

As far as I can recall the high beam selector is a standard GM affair, pull the turn signal lever back until it clicks and high beams are on, pull it back again until it clicks and it turns on the low beams, if you hold the lever back both the high beam and low beam are illuminated. The multifunction switch is working correctly, I get high and low beams as expected. I haven't tried pushing the lever away, but in other GM vehicles this would break the lever before it flashed the high beams, I'll try it when I get home tonight, but it would be a serious deviation from any GM vehicle I've driven. The ambient light sensor is functioning properly, when covered the headlights turn on, when uncovered the headlights turn off, DRLs don't come on when ambient light is bright, I don't think I have a light brighter than the sun but I suppose I could try shining a flood light on the sensor.

[astroturf]

Have you inspected the switch that engages when you apply the parking brake?

My Two Cents, Jim

[astroturf]

OK Now I got 4 cents for you. Did you buy this guys van?

viewtopic.php?f=76&t=6402&hilit=disable+drl#p53567

Also see this post:

viewtopic.php?f=76&t=6068&p=47822&hilit=drl#p47646

And then if push comes to shove... Go here to reverse engineer what someone else has done:

http://www.lightsout.org/disable.html

Hope it helps, Keep us posted, Jim

[kornphlake]

Now I'm getting somewhere, it's likely a problem with the relay that is hidden under the dash. I'll have to look for it tonight.

As far as I know I didn't buy a van that has been modified, I'm pretty sure the lights worked when we took ownership a couple months ago.

[mkj54]

Sorry I described the turn signal lever operation wrong, not sure what model or year I've seen work that way but it sounds as if the flash to pass is working fine . So that diode D300 is OK and the DRL relay is working. That leaves the BCM and the ambient sensor. There might be another input I'm missing in the diagram or something not shown. The BCM has to have a way to know when it's day lite to turn on the DRLs and when it's dark enough to go to regular head lites. And when DRLs are needed it needs to ground pin 10 at the DRL relay and open pin 10 when regular head lites are needed.

[kornphlake]

schematic1.jpg (75.36 KiB) Viewed 3131 times

So we're all on the same page, these are the schematics I'm looking at from the chilton library MKJ linked to. I cropped and realigned the first schematic to get rid of the sealed headlamp, I have the composite headlamp. The schematic has one flaw I've found, possibly more. Fuse 4, the gage and DRL relay fuse is not hot at all times, it's only hot when the key is on. The schematic I have for a blazer shows that this fuse should only be hot with the key on, the Saturn SL manual I have confirms. I'm not surprised Chilton made a mistake, but it was a little bit of a frustration.

Alright here's what I've found probing the DRL relay:
with the key off
*6, 9 and 8 are all NC
*7 is ground
*10 is NC.

With the key on
*6 is hot
*8 and 9 are NC
*7 is ground
*10 is NC

With the key on and headlights on
*6 and 8 are hot
*9 is NC
*7 is ground
*10 is NC

With the key on, transmission in gear, lights off
*6 is hot
*8 and 9 are NC
*7 and 10 are ground

With the key on, transmission in gear, lights on
*6 and 8 are hot
*9 is NC
*7 is ground
*10 is NC

Lights were switched using the control on the dash as well as the ambient light sensor, where specified above as lights off a light was put on the ambient light sensor to force the lights off even though it was getting dark.

It looks like pin 9 is never getting power, but there's that diode in there, I'm not sure I understand what its purpose is.

So far I've confirmed the DRL relay is working properly, I switched the DRL relay with the other relay next to it that keeps the accessories on until a door is opened, both relays function properly in that socket. The ambient light sensor is working properly (which isn't shown on the schematic,) the knob on the dash is working properly, the steering column multifunction switch is working correctly, the parking brake switch is working correctly (which isn't shown on this schematic) the flash to pass seems to work, I'm not sure I'm using it correctly, but if I pull the turn signal lever back but not far enough to click the lights will momentarily turn on. I'm suspicious the diode has gone bad and is blocking current in both directions, or there's a loose connection somewhere on the white or yellow wire that attach to the diode. Where in the heck is that diode located???

Option #2- The schematics I have for a blazer and saturn show a DRL module rather than the BCM controlling the DRL relay, the schematics are much more involved and include switching from the ambient light sensor, parking brake and gear selector. I have a feeling that there is too much missing from the schematic above.

[mkj54]

Maybe this can help.


Re: DRL WON'T COME ON
Posted: January 29th 2010, 3:32amby Astroplane
When you get the DRL wiring diagram in front of you, look for a 2 wire (Yellow, Orange) DRL diode on the schematic. If you have this on your van check for one or two burned/melted connector cavities at C200 which is the 2 row multi wire connector close to the e-brake pedal. Tonight I spent 3 hours diagnosing my '97 DRL's with the FSM and wound up removing the intermediate bench seat and driver's body side lower trim panel (AKA Rear heater core cover) to get a test light on the orange wire. The DRL diode lives in the rear of the driver's door pillar. Awesome place for a headlight/safety component. After confirming continuity between the diode and the I/P fuse panel (DRL fuse #15) I realized that I had somehow made the circuit OK for a moment and was jiggling connector 200 to check for a bad connection when the DRL's came on. Both Yellow and Orange wires are next to each other and were severly overheated melting the plastic connector. Hindsight being 20/20, the FSM was absolutely correct when it said to check for an open on the orange wire from DSL diode to I/P fuse panel. If the 2000 autolights wire diagram seems to conflict with my info then please disregard this.

viewtopic.php?f=76&t=5778&start=0&view=print