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Question

both of my headlights stop working at the same time. my day time running lights still work but when i turn the headlight knob to put on the regular headlights. all the lights turn off . so i have to put the knob in the middle position so the day time headlights stay on at nights.

Submitted: 377 days and 21 hours ago.

Category: Chevy

Value: $15

Status: CLOSED

377 days and 21 hours ago.

Reply

1999 Chevrolet Tahoe 5.7Lt

Already Tried:
looking for fuse

Answer

Low and High Beams Headlamps Inoperative (Headlamps)
Step
Action
Value(s)
Yes
No
1
Did you perform the Headlights System Check?
--
Go to Step 2
Go to Headlight System Check
2
Disconnect connector C266.
Connect a J 39200 DMM, set on ohms, between connector C266, cavity E13 for CKT 10 (YEL), and cavity E12 for CKT 12 (TAN).
Operate the headlamp switch at least twice.
Is there continuity?
--
Go to Step 3
Go to Step 5
3
Disconnect the headlamp switch connector.
Connect a J 39200 DMM between C266, cavity E13, and the headlamp and panel dimmer switch connector, cavity G for CKT 10 (YEL).
Is there continuity?
--
Go to Step 4
Go to Step 6
4
Connect a J 35616-200 test lamp between the headlamp and panel dimmer switch connector, cavity C for CKT 42 (RED), and ground.
Does the test lamp light?
--
Go to Step 7
Go to Step 8
5
Repair an open in CKT 10 (YEL) or in CKT 12 (TAN) in the steering column.
Did you find and repair the condition?
--
Go to Headlight System Check
Go to Step 7
6
Repair the open in CKT 10 (YEL) between the headlamp and panel dimmer switch and connector C266.
Did you find and repair the condition?
--
Go to Headlight System Check
--
7
Replace the headlamp switch. Refer to Headlamp Switch Replacement
Is the repair complete?
--
Go to Headlight System Check
--
8
Repair the open in CKT 42 (RED) between the underhood fuse-relay center and the headlamp and panel dimmer switch.
Did you find and repair the condition?
--
Go to Headlight System Check

View Full Image

Step	Action	Value(s)	Yes	No
1	Did you perform the Headlights System Check?	--	Go to Step 2	Go to Headlight System Check
2	Disconnect connector C266. Connect a J 39200 DMM, set on ohms, between connector C266, cavity E13 for CKT 10 (YEL), and cavity E12 for CKT 12 (TAN). Operate the headlamp switch at least twice. Is there continuity?	--	Go to Step 3	Go to Step 5
3	Disconnect the headlamp switch connector. Connect a J 39200 DMM between C266, cavity E13, and the headlamp and panel dimmer switch connector, cavity G for CKT 10 (YEL). Is there continuity?	--	Go to Step 4	Go to Step 6
4	Connect a J 35616-200 test lamp between the headlamp and panel dimmer switch connector, cavity C for CKT 42 (RED), and ground. Does the test lamp light?	--	Go to Step 7	Go to Step 8
5	Repair an open in CKT 10 (YEL) or in CKT 12 (TAN) in the steering column. Did you find and repair the condition?	--	Go to Headlight System Check	Go to Step 7
6	Repair the open in CKT 10 (YEL) between the headlamp and panel dimmer switch and connector C266. Did you find and repair the condition?	--	Go to Headlight System Check	--
7	Replace the headlamp switch. Refer to Headlamp Switch Replacement Is the repair complete?	--	Go to Headlight System Check	--
8	Repair the open in CKT 42 (RED) between the underhood fuse-relay center and the headlamp and panel dimmer switch. Did you find and repair the condition?	--	Go to Headlight System Check

Accepts:
Expert:	Dan
Pos. Feedback:	99.0 %
Answered:	11/10/2008

Auto Technician

GM Mark of Excellence/ Service Guild Participant with 13 years experience, ASE Master Certified

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