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Need Help with a headlight module question

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Old Nov 15, 2007 | 10:32 PM
  #1  
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gillettij
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Default Need Help with a headlight module question

My left side headlight needs a gear replacement and I have the gears,
just haven't done it yet. It works and all just makes the grumble noise on closing.

Thr right side only comes up during the day when I use the signal lever to turn on the lights. At night it won't open at all. I am leaning toward the problem being the module. Just so happens, that there is a guy selling one on EBAY. Any input?

http://cgi.ebay.com/ebaymotors/ws/eB...ksid=p3907.m32

where are these things located on the car?
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Old Nov 15, 2007 | 10:36 PM
  #2  
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Oldvetter
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From: Waldorf MD
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Does the light come on for the right headlight when it doesn't come up? If so, I doubt it is the module.

The module is located under the passenger side headlight. They rarely go bad. They are over $200 new.

Here is the procedure to replace it (PM me your address and I will send writeup with pictures):

Document ID# 219626
1998 Chevrolet/Geo Corvette


--------------------------------------------------------------------------------

Headlamp Control Module Replacement
Removal Procedure




Remove the passenger side front floor kick up panel cover to access the instrument panel (IP) electrical center.



Remove the headlamp circuit breaker from the IP electrical center.
Open the hood.



Raise the RH headlamp manually.
Turn the headlamp motor/actuator manual control **** counterclockwise to raise the headlamp.
Disconnect the RH headlamp wiring harness electrical connector from the forward lamp wiring harness.



Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove the front fascia lower closeout panel. Refer to Close Out Panel - Front Bumper Fascia Lower in Bumpers.
Release the brake caliper cooling duct from the front fascia and reposition the duct.



Disconnect the electrical connectors from the headlamp control module.



Remove the nuts mounting the module to the headlamp bracket.
Remove the module from the vehicle.
Installation Procedure




Install the headlamp control module into position on the headlamp bracket.
Install the nuts mounting the module to the headlamp bracket.



Connect the electrical connectors to the module.



Position the brake caliper cooling duct to the front fascia and push to secure.
Install the front fascia lower closeout panel. Refer to Close Out Panel - Front Bumper Fascia Lower in Bumpers.
Lower the vehicle.



Connect the RH headlamp wiring harness electrical connector to the forward lamp wiring harness.
Lower the RH headlamp manually. Turn the headlamp motor/actuator manual control **** clockwise to lower the headlamp.



Install the headlamp circuit breaker into the IP electrical center.
Install the floor kick up panel covering the IP electrical center.

Last edited by Oldvetter; Nov 15, 2007 at 10:42 PM.
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Old Nov 15, 2007 | 11:06 PM
  #3  
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Oldvetter
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From: Waldorf MD
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Here is the diagnosis from the shop manual:

Document ID# 338185
1998 Chevrolet/Geo Corvette


--------------------------------------------------------------------------------

Headlamp Doors Inoperative - One Door
Headlamp Door Inoperative, One Side Step
Action
Value(s)
Yes
No

1
Were you sent here from the Headlight Door System Check?
--
Go to Step 2
Go to Headlight Door System Check

2
Disconnect the inoperative (left/right) headlamp connector.
Connect a DMM between the headlamp connector terminal A and terminal B.
Turn the headlamp switch to the ON and then the OFF position.
Measure the voltage at the DMM in both of the headlight switch positions.
Is the voltage within the specified values?
10.0-14.0V
Go to Step 11
Go to Step 3

3
Disconnect the headlamp opening door actuator control module connector C2.
Connect the positive lead of the DMM at the inoperative headlamp connector terminal B.
Connect the negative lead of the DMM at the headlamp opening door actuator control module connector terminal:
Left Side = terminal A
Right Side = terminal D
Measure either of the following circuits for continuity between the headlamp connector and the headlamp opening door actuator control module connector.
Left Side = CKT 576
Right Side = CKT 578
Is the relative circuit continuous between these two terminals?
--
Go to Step 4
Go to Step 7

4
Connect the positive lead of the DMM at the inoperative headlamp connector terminal A.
Connect the negative lead of the DMM at the headlamp opening door actuator control module connector terminal:
Left Side = terminal B
Right Side = terminal C
Measure either of the following circuits for continuity between the headlamp connector and the headlamp opening door actuator control module connector.
Left Side = CKT 577
Right Side = CKT 579
Is the relative circuit continuous between these two terminals?
--
Go to Step 5
Go to Step 8

5
Connect the positive lead of the DMM at the inoperative headlamp connector terminal B.
Connect the negative lead of the DMM to ground.
Measure either of the following circuits for continuity to ground.
Left Side = CKT 576
Right Side = CKT 578
Is the relative circuit shorted to ground?
--
Go to Step 9
Go to Step 6

6
Connect the positive lead of the DMM at the inoperative headlamp connector terminal A.
Connect the negative lead of the DMM to ground.
Measure either of the following circuits for continuity to ground.
Left Side = CKT 577
Right Side = CKT 579
Is the relative circuit shorted to ground?
--
Go to Step 10
Go to Step 12

7
Repair a poor connection or an open in the circuit relative to the inoperative headlamp door.

Left Side = CKT 576
Right Side = CKT 578
Is the repair completed?
--
Go to Headlight Door System Check
--

8
Repair a poor connection or an open in the circuit relative to the inoperative headlamp door.

Left Side = CKT 577
Right Side = CKT 579
Is the repair completed?
--
Go to Headlight Door System Check
--

9
Repair a short to ground in the circuit relative to the inoperative headlamp door.

Left Side = CKT 576
Right Side = CKT 578
Is the repair completed?
--
Go to Headlight Door System Check
--

10
Repair a short to ground in the circuit relative to the inoperative headlamp door.

Left Side = CKT 577
Right Side = CKT 579
Is the repair completed?
--
Go to Headlight Door System Check
--

11
Replace the inoperative headlamp opening door assembly.

Is the repair complete?
--
Go to Headlight Door System Check
--

12
Replace the headlamp opening door actuator control module.

Is the repair complete?
--
Go to Headlight Door System Check
--
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Old Nov 16, 2007 | 11:08 AM
  #4  
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dgrant3830
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Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
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On my '99, I was having the headlamps not come up at all which turned out to be the headlamp switch itself. But right after that, the headlamps would turn on, but not raise....that turned out to be the module, but it was both headlamps, not one.
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