Dash backlighting

[Guest Earl Filippelli]

Hello all,

Thanks for the info on the bad diode my lights work fine now. 1988 reatta none of the lights in the switches next to the spedo come on with the headlight switch,same with the shift console lights,the console lights do come on with display on enter then go off.Also the spedo gas and touch screen stay bright,the dimmer does not make any change.I have changed the headlight switch unit.

[DAVES89]

From what you are posting the console lights up during the "light show", but not either the headlight or wiper switch pods. That is the nice thing about "the show", it is a self test designed into the car and tells/shows you what works and what doesn't. If it lights up during the show it works if it doesn't it's broke.So you may have to replace both pods.

Either at night or when it is dark turn on your lights. If nothing [headlight/wiper pods and console]lights up,I believe it would be the photocell located on the top middle of your dash that is bad. There is a tutorial about that under my posts back on 8/29/2007.

[harry yarnell]

I thought that the photocell was used for the Twilight Sentental. The '88 doesn't have Twilight Sentenal.

[Guest tomt]

Jim Finn, at the Illinois Regionals had diagnosed that my back light problem was probably due to the inverter used for that system, and I think that may be the problem here.

Jim sold me an inverter, but as time went on, I find that my pod lights work probably 60% of the time, so hesitated to replace a part that works a good portion of the time with a used one. Over all in the enjoyment of the vehicle, I began to think how important is it really?

TT

[DAVES89]

Sorry, I have an '89 and spoke about what worked for me. The '88 does not have twilight sentinal.

[Jim]

From 10 years of experience with Reatta parts, it is your headlight switch module.

Twilight sentinel was an option on the '88-90 Rivieras but not on the Reattas until '91.

I used to say the most common part to go bad in the '88-89 Reattas was the CRT/touch screen but now I believe that is second and the headlight switch module is the most common part to go bad. This module is made up of metal sliders and contacts which can wear out and get dirty.

Two items I have mentioned in the past.

One, do not buy a used switch on Ebay unless the seller specifically states that the dimmer slider works and the background lights on the CRT, console and wiper switch module work.

Second, I have purchased about 40 used switches from junk yards with only about 8 of them working the first time and then after cleaning only about a 20% success rate with the cleaned ones.

The inverters and/or the twilight sensor up near the windshield do go bad but in my opinion 99% of the time it is the headlight switch module.

I do have some good tested working switches available and can be reached at jfinn@cpinternet.com