How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask GM Tech (Cam) Your Own Question

GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 27661
Experience:  GM Grand Master Technician 2007. 11 years experience.
Type Your Chevy Question Here...
GM Tech (Cam) is online now
A new question is answered every 9 seconds

1999 chevy tahoe: Interior lights..doors..Dome Light..Instrument Panel

Resolved Question:

1999 Chev Tahoe. Interior lights not working properly:
- Courtesy lights do not turn off after doors close
- Dome lights and reading lights do not illuminate
- Dome Light Override switch checks out
- Park and Head lamps work properly
- Instrument Panel Dimmer switch works but does not turn on Dome lights
Submitted: 4 years ago.
Category: Chevy
Expert:  GM Tech (Cam) replied 4 years ago.

Welcome. I will try my best to help you and in order to do that, I need you to describe as best you can because I only know as much about your problem as you have told me in your post, so my answer will be based on what you have posted. Please feel free to reply as needed.

Let try some testing. Take the switch out and find the white wire in terminal M. Ground this terminal and see if the lights turn on.

Customer: replied 4 years ago.

I tested the white wire to ground as part of the override switch test. When the override switch is in the ON positiion the white wire is connected to ground. When in the OFF position it is opn to ground. I did not check this with power on.

 

The concern is that the courtesy lamps do not go off so I have to remove the fuse to keep the battery from running down. Plus when I turn the dimmer switch to full on, the courtesy lights get brighter but the dome lights do not come on.

Expert:  GM Tech (Cam) replied 4 years ago.

OK, lets tryt he diagnosis below.

Courtesy or Dome Lamps Always On (Except Luxury)

Step

Action

Value(s)

Yes

No

DEFINITION: Use this diagnostic in order to diagnose the Dome and/or Courtesy Lamps Always On with all vehicle doors closed and the dome lamp switch in the OFF position. On vehicles equipped with remote keyless entry or an interior lamp control module will cause the interior lamps to remain in the ON position after the door is opened for approximately 40 seconds or until an ignition ON cycle has occurred.

1

Did you perform the Interior Lamps System Check?

--

Go to Step 2

Go to Interior Lamps System Check

2

  1. Close the vehicle doors.
  2. Disconnect the headlamp and the panel dimmer switch.

Do the courtesy and/or dome lamps turn OFF?

--

Go to Step 3

Go to Step 7

3

  1. Close the vehicle doors.
  2. Connect a J 39200 , set on Ohms, between the headlamp and the panel dimmer switch connector cavity L and ground.

Is there continuity?

--

Go to Step 5

Go to Step 6

4

Is the vehicle a suburban/utility with cargo doors?

--

Go to Step 12

Go to Step 5

5

  1. Repair the short to ground in CKT 328 (PPL) between the headlamp and the panel dimmer switch and door jamb switches.
  2. If no short to ground is found, replace the faulty door jamb switches.

Is the repair complete?

--

Go to Interior Lamps System Check

--

6

Replace the headlamp and the panel dimmer switches.

Is the repair complete?

--

Go to Interior Lamps System Check

--

7

Disconnect the interior lamp control module or the keyless entry module.

Do the courtesy and/or dome lamps turn OFF?

--

Go to Step 8

Go to Step 11

8

Connect a J 39200 , set on Ohms, between CKT 157 (GRY) at cavity B of the interior lamp control or cavity K of the keyless entry module and ground.

Is there continuity?

--

Go to Step 9

Go to Step 10

9

Repair the short to ground in CKT 157 (GRY) between the headlamp and the panel dimmer switch and wither the interior lamp control module or the keyless entry module.

Is the repair complete?

--

Go to Interior Lamps System Check

--

10

Replace the interior lamp control module or the keyless entry module.

Is the repair complete?

--

Go to Interior Lamps System Check

--

11

Repair the short to ground in CKT 156 (WHT) between the headlamp and the panel dimmer switch and the dome and/or courtesy lamps, the interior lamp control module or the keyless entry module.

Is the repair complete?

--

Go to Interior Lamps System Check

--

12

With a J 39200 still connected at the headlamp and the panel dimmer switch cavity L and ground, disconnect the door lock control module.

Is there still continuity?

--

Go to Step 5

Go to Step 13

13

Connect a J 39200 , set on Ohms, between the door lock control module connector cavity F and ground.

Is there continuity?

--

Go to Step 14

Go to Step 15

14

  1. Repair the short to ground in CKT 1897 (ORN/BLK) between the door lock control module and the rear door jamb switch.
  2. If no short to ground is found, replace the rear door jamb switch.

Is the repair complete?

--

Go to Interior Lamps System Check

--

15

Replace the door lock control module.

Is the repair complete?

--

Go to Interior Lamps System Check

Customer: replied 4 years ago.
I have done many of the checks listed, but not all. One thing that you said has my interest. I have a general schematicfrom Haynes that shows an Interior Lamp Control Module. That looks to be the problem as the timer and ignition cut off for the courtesy lights is not working; however, I called Chev Parts this morning and they do not list this module as a separate part. Is it contained in the light switch assembly or is it a separate part?
Expert:  GM Tech (Cam) replied 4 years ago.

It is separate. It is under the left side of the dash by the remote control door module. It is #2 and the remote control module is #3

Object Number: 278106  Size: MF

Customer: replied 4 years ago.

Is there a place to get an actual schematic for this circuit?

Expert:  GM Tech (Cam) replied 4 years ago.

Object Number: 366442  Size: FSObject Number: 366461  Size: FS

 

 

GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 27661
Experience: GM Grand Master Technician 2007. 11 years experience.
GM Tech (Cam) and 6 other Chevy Specialists are ready to help you
Customer: replied 4 years ago.
Thank you very much

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I was having a terrible problem with the wheel bearings on my 98 Chevy Cavalier and I suspect that using this website saved me plenty of time and money. Todd L Rochester NY
< Last | Next >
  • I was having a terrible problem with the wheel bearings on my 98 Chevy Cavalier and I suspect that using this website saved me plenty of time and money. Todd L Rochester NY
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
  • Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
  • Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
  • Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
 
 
 

Meet The Experts:

 
 
 
  • Tim's Auto Repair

    mechanic

    Satisfied Customers:

    7641
    Have owned a repair shop for 25 yrs.
< Last | Next >
  • http://ww2.justanswer.com/uploads/TI/tim37857/2011-10-28_23053_S6301814.64x64.JPG Tim's Auto Repair's Avatar

    Tim's Auto Repair

    mechanic

    Satisfied Customers:

    7641
    Have owned a repair shop for 25 yrs.
  • http://ww2.justanswer.com/uploads/DT/dt69nova/2012-6-15_234154_pic1.64x64.jpg Dave Nova's Avatar

    Dave Nova

    Chevrolet Technician

    Satisfied Customers:

    6870
    ASE Master Certification. GM World Class Certification
  • http://ww2.justanswer.com/uploads/ggrote1/2009-06-27_031011_me.jpg Gary's Avatar

    Gary

    Chevy Technician

    Satisfied Customers:

    5404
    15 years GM master tech
  • http://ww2.justanswer.com/uploads/testedtuff/2009-09-26_170108_pictures.jpg John's Avatar

    John

    Master A.S.E Automotive technician

    Satisfied Customers:

    4071
    A.S.E MasterTechnician A1-A8 w/L1,38 years experience General Motors Master Technician
  • http://ww2.justanswer.com/uploads/RO/rodcuda/2011-7-25_224114_Donhoff1.64x64.JPG Neal's Avatar

    Neal

    Chevy Mechanic

    Satisfied Customers:

    2306
    Shop Owner and Mechanic on multiple makes.
  • http://ww2.justanswer.com/uploads/goodwrench9124/2008-11-09_220838_dscf0007.jpg goodwrench9124's Avatar

    goodwrench9124

    ASE Certified Technician

    Satisfied Customers:

    2041
    Ase Master Certified, GM Master Certified Tech. Awarded GM Top performer, Hybrid certified
  • http://ww2.justanswer.com/uploads/DR/drivefast1971/2012-1-12_172422_0009051tQKh.64x64.jpg Ron Z.'s Avatar

    Ron Z.

    - Chevy Tech -

    Satisfied Customers:

    1912
    18+yrs experience. State Inspector and Chevy Diagnostics