1996 Tahoe 2 dr. Dash Rear Wiper and Hatch switch lights not working?

[RangerZ71]

96 2 door Tahoe dash rear wiper and hatch switch lights not coming on with headlight switch on. All dash and courtesy lights work. I've checked for power on the grey switch wires and have no power with light switch on. The switches work fine for operation, rear washer and wiper work and the hatch opens like it should, just no lights on the switch? Any help would be appreciated.

 

[east302]

Here are the wiring diagrams for a 96. Do you get no voltage on the gray using both the harness ground and a chassis ground? The radio lights share the same circuit, so if they work that should narrow it down somewhat. Voltage should drop to zero as the headlight dimmer switch is turned down.

If you get that far, the switches can be disassembled and the bulbs replaced. I used the same ones as the radio button lights - seems to work just fine.

 

[RangerZ71]

east302, thanks so much for the schematic, great! Upon further work, it has turned out that the bulbs were burned out in both switches!! I'm in the process of trying to replace the bulbs with the led 3mm style. I did get a couple more switches from the salvage yard. out of 2 of each I did get a pair that works!! I bought this Tahoe brand new and the only driver.
I keep it up meticulously! the years of age has really started to catch up.
With your post I can easily check the circuits now. Thank you again.
I would like to get more air flow from the A/C blower as the flow is terrible in the heat of summer. I've checked the air box and it is clean with no visible crap. Motor runs on all speeds too. Air is cold also. I would think the issue is probably leaking doors inside the box, doors work properly with controls. I can't fix that I don't think. If there was a stronger blowing motor I think I would go for it.

 

[east302]

Glad you got it sorted out.

The air dampers have rubber seals along the perimeter which tend to rot away and let air flow by - particularly to the floor when the dash vents are selected. Once you pull the dash, they’re easy enough to replace and the GM parts are still available. It helped some in mine, but airflow is still pretty poor compared to anything new today. Even the generation after ours was a vast improvement in the blower department.

By design, some air is sent to the windshield and side defrost vents at all times. Seems like a waste of air when every little bit counts, but that’s the way they did it.

The best solution that I’ve found is to close the two passenger vents when I’m driving. If your heater hose valve isn’t working, that’s worth fixing. It closes coolant flow to the heater core when the temperature dial is in the “max” detent and can lower vent temperatures by a degree or two.

 

[RangerZ71]

True on all on A/C! I do the same in hot summer on vents. Shame their is no stronger blower motor available that could push more air through the box. I know mine leaks air because windshield fogs up in the center area with air on. I put a card board sheet over it in the summer! You right everything helps on putting more air to the driver.
I have one more item. My driver door lock actuator went bad, I replaced it and the new one is hit and miss on unlock, locks every time. I can hear it try to unlock every time also. I try it 3-4 times and it will unlock. Since I hear it try to actuate every time my thoughts are the solenoid just don't push the rod to unlock every time and even new it could be defective. Also since I hear it try to unlock, I think the electric circuit is ok. Any experience or other suggestions.

 

[Eman85]

The locks have decades of dirt in them. First give it a good cleaning and lube it see if it responds.