Hi,

I will try to describe recent events that I was told by my wife in regards to her T&C and a possible battery issue. I work out of state and won't be home until tomorrow.
She waited for a school bus with emergency lights on for about 30-45min. After that she started the van but it wouldn't. A friend offered her a boost and she managed to get back home. She tried to restart the van again later at night and it wouldn't again. The next day a friend came in and hooked up a charger for about 6 hours. The van started but at some point later started chocking and the dashboard lights started blinking. I asked her to run the van last night for about 10 minutes so the battery could recharge. So, this morning the van started, the dashboard lights worked but the headlight are gone. They don't work. She stopped at Autozone and had the battery and alternator checked and they both turned out OK.
I'm puzzled but I'm convinced 100% that this battery is dying. However i still don't understand why the head light are not working. Also is the van didn't start only after being on emergency light for about 30 minutes that would suggest me that the battery is definiately going bad.
Any idea what in the world is going on? What am I looking at? Is there something else that could have gone wrong? Why would Autozone test proof that both battery and alternator are OK.
I appreciate your suggestions.
Thanks

 

Bit late now but it's advisable to get the electrical system checked out at the first sign of trouble. Today's autos need clean steady voltage due to the sensitive electronic components used today. Waiting can produce strange symptoms and sometimes damage.

Pretty good bet your battery is on it's way to that big battery pile in the sky especially if it's the original battery. Parts store testing isn't ironclad.That or you have corroded or loose battery connections. There is a history of battery cables coming loose from the battery terminal connectors. Have someone take a close look.

Your headlights are controlled by the Front Control Module (FCM) via the switch. It's the silver box mounted to the IPM (fuse box). Your battery issue may have confused or damaged it. Changing the battery may solve the issue but in the mean time you can try disconnecting the negative battery cable for 5 minutes. This may reset the control circuit.

 

Also.....you don't need battery power once the vehicle is running. So, there must be some other issue besides the battery, which is probably why the battery is in such bad shape. Since they said the charging system is working fine, check all terminations and connections. Just like Cougar said, look for loose or corroded connections. Although, as mentioned, their test isn't a guaranteed....did they do a load test on the charging system or just check the voltage? I would feel better about a load test.

In the end, by replacing the battery, they/you may inadvertently tighten a loose connection and fix everything. Clean and tighten your battery connections....that means remove the cables from the battery posts and clean the connecting surfaces before putting them back on.

 

OK - Thank You both for all suggestions.
I replaced the battery anyway to be on a safe side and the head light still don't work. I flipped my service manual for T&C to learn what FCM controls. From the list it appears that all (so far I don't see any problems) components work like wipers, fans, heat, etc. The light switch has two stages. When switched to first stage the orange lights turn on. The turning light work as well. When switched to second stage (headlight) then I get nothing. I just run outside to check if high beam work and guess what ...it works. So I don't get why the low beam doesn't work. I checked all fuses and they are OK. Unfortunately didn't have time to check relays. The van runs fine and battery / charging voltage is OK. So what's the next step? Can FCM be reprogrammed or replaced from another vehicle if that's the problem? I checked the connections for loose or rusted spots and cannot see anything. I live in Atlanta area and the engine compartment looks very clean and rust free.

 

Try a new headlight bulb before starting expensive testing. While it is unlikely, I have seen 2 headlights go within a short time of each other and the voltage spikes from jumpstarting could have damaged them.

@kinfofwylietx: Yes you DO need good battery power at all times. The alternator would not last very long if it were the only source of electricity.

 

You can check the bulbs with an ohm meter. Pin 2 is ground. Pin 1 is low beam. Pin 3 is high beam. If there's infinite resistance meaning value doesn't change, you need a new bulb.

No relays in the headlight circuit. Switch, BCM, IPM, FCM, light assembly, bulbs and wiring connectiong it all is it. Would you like the wiring diagram? Send me a PM with an email address.

 

The most common problem will be the light bulb. Just pull it out, and look at the Filament.
2nd common problem is the Head light switch itself. Without scanner, it is hard to test the headlight switch other than just throw a new one in.

 

I visually checked one bulb when I replaced the battery. I couldn't see broken ligament so I assumed that they are still OK. I also measured the voltage inside the light bulb socket with the switch on and got nothing. I will try another bulb but I'm positive this is not it. These are Philips Crystal vision and they have been changed just about 3 months ago,
From your responses I understand that the FCM is still OK and most likely something else is gone. Can the switch only be replaced or is it a part of another assembly? Which fuse controls the head lights
Thanks.

 

The headlights don't have fuses either individually or as a group. The FCM powers the lamp socket via the IPM (fuse box). It's still on the list of possibilities. The switch via the BCM tells the FCM when to apply that power. Just for grins try wiggling the IPM/FCM and connections and watch for the low beams to come alive.

Usually I pass this info on when a single headlight won't turn on on a 4th generation van. I have doubts this is the cause of your problem because the chances of two contacts failing simultaneous are low. That said it wouldn't hurt to check just to be sure. Power for the headlights exits the FCM and enters the IPM on what are called spade contacts. This connection between the FCM and IPM is a poor design causing a variety of lighting problems. It easily corrodes and the contacts contort and get misaligned. To check it disconnect the negative battery cable then remove the four bolts securing the FCM to the IPM. Remove the FCM and inspect for corrosion. Clean it with contact cleaner. With a pair of needle nose pliers slightly twist/bend the spade contacts for the low beam lights, contacts 3 & 6. These are wide and flat contacts. Reassemble and check the lights.

The IPM itself is a know corrosion magnet. Check connections for corrosion.

 

Thanks Cougar!
One more question before I'll start ripping everything off.
Is it worth testing the headlight switch alone? I mean ... what are the chances of this switch going bad? I found in my manual the resistances between pin outs so I'm wondering if something got shorted or ???
I'll flip the whole fuse box tomorrow and will let you know the results.