martyw61

I have a 2000 chevy malibu with headlight problems. Low beams do not work. High beams work correctly. I've replaced bulbs with no change. I have swapped the relays with no change. I have power to the bulbs. I suspect a ground problem but cannot locate the ground cluster. Suggestions?

mack1

Hi Marty and welcome to TSF,

I just happen to have a Haynes repair manual that covers your year. The electrical print shows that power is always applied to the high and low beam at the bulbs. A 15 amp fuse survices the left side and another one services the right side. Each fuse services both its high and low beam. The hot wire to the low beam is orange. The ground wire on each low beam is dark blue. The switching occurs on the ground side of the bulb. ( all the way through the dimmer switch to get to the ground cluster.) The dark blue wires go from the low beam lamps to the Under Hood Junction box. There are four total wires there, all joined together. One of the other dark blue wires goes to the Turn/Headlamp/Switch Assembly. I think that switch is on the stearing column. The fourth Dark Blue wire goes to the Body Control Module (not sure why unless it is involved in turning the lights off after a delay.)

The same conection scheme is used for the high beams. The ground side wires are pink. As above, to the Under Hood Junciton box, Grouped together there, one pink wire to the Headlamp Switch, and one to the Body Control Module. I'll post again with some pictures. Have to do it with a digital camera so it will take a little while.

Best regards,
Mack1

mack1

Hi Marty,

Below are three pictures that pretty much shows all the wiring associated with the headlights.

Click on the pictures to enlarge them.

Picture 1 shows the Underhood Junction Box and the right side high and low headlamps. Left side Headlamps are out of the picture on the left and exactly like the right side. Notice that the positive side of the lamps are always hot and the bottom (ground) joins with the other dark blue leads at the Underhood Junction Box. If you shorted the dark blue wires at that point, the low beams should come on. If not, the problem is toward the lamps. If they come on, the problem is below.

The second picture shows the lower part of the print. Two dark blue wired come down, one to the Headlamp switch at the lower right and the other to the Body Control Module at the left side. Notice that a ground wire that is common to both the high and low beams extends from the Lamp switch to a ground cluster.(the ground point for both the high AND low beams. Since the high works, the problem is not there. The problem is either in the dimmer switch or above it.

The third picture is a close up of the Lamp switch. The lower part is the on/off switch and the upper part is the high/low beam selector. Notice that it also contains an extra high beam point used to request dim from an oncoming vehicle.

Hope this helps.

Have a nice day,
Mack1


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martyw61

Thanks for information Mack-I'll look for the grounding point and let you know what I find. The problem is its my daughters' car I don't get to work on it as often as I would like.

gtorob

Mack please post more of the wiring for the 200 malibu my Wife's car has low beam on the left side that just won't work and now the DRL are out. The right low beam is fine and so are the high beams. Can you scan the rest please?

thank you!

mack1

Hi guys,

Welcome to the forum Rob. Normally we ask each person to post their own thread, but since each of you have very similar problems, we can all use this thread.

To make a hardcopy of each print, do this.
1. Click or double click on each picture, it will expand.
2. While expanded, right click on it and pick "copy".
3. Then open up "paint" on your computer.
4. Under the "edit' tab, select "paste".
5. Under the "file" tap, select "save as".
6. On that window at the top, navagate to where you want the picture placed. (desktop will put an icon on the screen for you)
7. On the bottom of that window, give the picture a name and type (jpg is good).
8. Then click on save.
From there, just print it out. Helps to have hardcopy while trouble shooting at the car.
I'll take another look in the book and see what I can find soon. I have a couple of chores to do now.

Best regards,
Mack1

gtorob

Here ya go guys a friend of mine has the ALLDATA software which has wiring diagrams. I wish I could get the original GM shop repair manual to really troubleshoot it. I know these were around $80 from GM originally and they can be found at flea markets as well as I got one for my old Pontiac GTO's. See if these attachments are ok.

Attached Images

200malibu-headlight.jpg (501.3 KB, 12 views)

mack1

Hi Rob,
Nice print. It is the same one I have in the Haynes book. I zoomed in with the camera so the printed data would be large enough to read. I also went to Alldata to have a look. I had a 98 Malibu subscribed there, but it is expired, so no help. The nice thing about Alldata is that the information you get is specifically for your vehicle, not several like in the regular maintenance manuals at auto parts stores. On a 96 S10 blazer, I found a parts locator sheet that tells where every part is on the car. I have found that to be helpful. My Haynes book has some pretty good info on how to take the plastic parts off in the dash area. I never know where to prize in order to get the parts off in one piece.

I didn't find any other electrical prints for the headlamp circuits. I think that is all you need to find the problems.

Below are three pics that might be of help. They deal with the light switch (multifuncton switch). Also backprobing using straight pins. I find that you need a pair of pliars to get the pins in far enough to make contact.

Best regards,
Mack1

HeadlampMallibu 001a.jpgHeadlampMallibu 005a.jpgHeadlampMallibu 006a.jpg