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Door ajar and other interior lights flash for 20-30 seconds. '97 Chrysler LHS

When this LHS is first started, I hear a clicking noise similar to the sound the directional flasher makes. The DOOR AJAR light on the message panel also flashes as do the dome lights and the temperature displayed on the A/C and heat controller. The clicking is not the same clicking as the directional and hazard lights flasher as that clicking sounds separately when the directional indicators or four way hazard lights are turned on. The car has big push button switches in each door jamb that operate the dome lights just like a car from the '50s. Once the clicking has stopped, those switches operate the dome lights normally. If I turn off the ignition for a moment, and start the car again, the clicking and flashing interior lights start in again. It is only really annoying when it’s dark, and might catch the attention of a police officer.

I have had Tauruses with similar symptoms that I fixed by spraying contact cleaner into the door latch mechanism, but Tauruses don’t have any dome light switches in their door jambs. I’ve tried spraying the cleaner into the door latches on this car, but nothing has changed. Does the LHS even have switches there?

A recent discussion about remote starters made me wonder if this might be related. The car does have a working after market remote starter and alarm system made by Ungo. Also, the power locks don’t all work, remotely or otherwise. They try to move the locks, but the gears in two of the actuators must be stripped. I don’t THINK that’s part of the problem, but it might be. I can live without power locks.

Does anyone here have any ideas as to anything that might be causing this situation?

All the displays and lights that are flashing are controlled thru the body control module.

Tester

^
+1!

While it is possible that the remote starter is to blame, my money is on a defective BCM.

Will a BCM click like that?

The BCM also controls the Park Lamp Relay.

That’s where the clicking is probably coming from.

Tester

My guess, it’s probably a faulty door switch or the wiring to the switch is faulty. The door switches are inputs to the BCM.

It could be any of the 4 doors that is causing the problem. Spraying contact cleaner is worth a try, but often won’t correct a door switch on the fritz.

@Tester might the issue be that relay, or is the signal provided to the relay by the faulty BCM ? When I started it in the dark a little while ago, I noticed that the side marker lights, not the brighter parking lights, were also flashing.

Aftermarket alarm systems do that. Remove the knee bolster and you’ll find a control module and a couple of relays stuffed in there. Will it stop flashing if you push unlock on the aftermarket remote?

I find that when reconnecting a battery some aftermarket alarms will flash a silent alarm for a minute, no horn. It may be that the system on your car is not wired correctly or has lost it 12 volt constant power source.

I don’t believe I have ever seen a LH BCM cause this.

The BCM provides the voltage to the primary side of the relay making the relay operate.

If the side marker lights are also flashing, check and see if the rear license plate light is also flashing. If it is, those lights are also controlled thru the BCM.

Gee! I wonder what’s causing the problem?

Tester

In think @Nevada_545 has nailed it. I had been unlocking it each time with a key in the door since the power lock doesn’t work. This morning I tried it by clicking the fob to unlock the drivers door. The lights flashed once outside. Then I unlocked the door with the key, got in and started it. The interior lights did not flash as they had been. I shut it off, got out, locked it, and tried it again with the same result. I guess what I need to do is fix the power lock actuator and always open it with the fob.

I have a number for a local Ungo distributor. I’llI try to find time to call them later to see if they can offer any suggestions.