Mechanics

HEADLIGHTS NOT WORKING

1997 Dodge Caravan

Electrical problem
1997 Dodge Caravan 6 cyl Two Wheel Drive Automatic 160000 miles

my 97 dodge caravan has a problem with its headlights I start the van and turn on the headlights and they will not come on but if I pull the high beam switch they come on but only if I hold the switch I know it is not a fuse any one have any ideas?
Avatar
Biggkenny419
March 23, 2009.



Just found the service manual. This procedure is different than what I remembered: ACTUATOR CALIBRATION TEST

Set blower motor on High.

Set Mode position to Panel.

Open all AC outlets.

Set temperature to cold.

Press Wash and Rear Wiper buttons at the same time for five seconds until all leds flash.

All leds will turn on for five seconds.

The calibration test is running when the Rear Wiper and Intermittent leds are flashing alternately.

Acceptable result is the Rear Wiper led is the only one flashing. Press Rear Wiper to exit. At this point, the calibration and cooldown procedures can be run separately.

COOLDOWN TEST

Set the blower motor on High.

Set mode to Panel.

Open all AC outlets.

Set the temperature to cold.

Press Wash and AC at the same time. (See note at the end).

Then there's a note in the manual that says the test will fail if the ac evaporator is already cold. HUH? &Quot; To correct, operate system with AC OFF and the blower motor on high for three minutes prior to starting the test". That's probably why I remember putting the temperature to hot before starting this test.

All leds will turn on for five seconds.

Cooldown test is running when AC and Recirc. Leds are flashing alternately. If they flash at the same time, the test has failed.

To abort the test, press the Rear Defogger, Recirc, and Rear Wiper buttons or cycle the ignition switch off and back on.

The manual doesn't say what to do next, but as I recall, if the test passes, only the AC led will be flashing. Press it to exit the procedure.

Note: For the Cooldown test, the manual say to " Press Wash and AC at the same time". Later, it says " Cooldown test is running when AC and Recirc leds are flashing alternately". To start the test, I think they meant press the AC and Recirc buttons, not the AC and Wash buttons. Try it both ways if you have to.

Caradiodoc

Caradiodoc
Mar 24, 2009.
Sorry, that previous comment was for a different post.

For your headlights, do you have fog lights and do they work? If they do, both of your low beam headlamp bulbs are burned out. Pulling on the dimmer switch and holding it turns on the high beams.

There are four separate fuses for the headlights. The fog lights also run off two of the fuses, so blown fuses would affect them too. It's unlikely two fuses would blow at the same time.

There are two headlamp relays. Try switching the high beam and low beam relays. If only the low beams work now, the other relay is defective.

The low beam relay is controlled by the Daytime Running Lamp Module for Canadian vehicles, or the Body Control Module for U.S. Vehicles. Great! Another over-complicated, unreliable computer to perform a simple operation. Now's the time to pay up for another unnecessary computer! Let's hope it's just a relay or two bulbs.

The headlight switch sends a voltage to the Body computer; the Body computer grounds the low beam relay. From looking at the diagram, it looks like the high beam relay uses common sense and is simply grounded to the body, so the high beams should still work if the Body computer is defective.

Replacing the Body computer is not a do-it-yourself project. It is bolted to and plugged into the Junction Block above the brake pedal. Try the relays and bulbs first.

Caradiodoc

Caradiodoc
Mar 24, 2009.