master window switch?

[aquaman0001]

Hello All,
The windows on my 99 Suburban are not going down when I try to open them with the master control switch. My first assumption is to replace the master control switch. But I want to make sure it is not anything else first.
Symptoms:

Windows sometimes do not go up or down with master control switch
Windows will not go up or down when tried with switch at window
Happens more when it has been very hot.

If the master switch is faulty, will the other window switches also fail to work?

Any suggestions will be greatly appreciated. Its a pita when you cannot put down the windows when its 99 degrees outside.....

A

[DmaxMaverick]

The most common cause is simple. Connectors and/or contacts. Remove the switch cluster from the door, disconnect the connector and inspect. You will probably see a dull/powdery residue on the poles/slots. A light brush with fine sand paper cleans them up well. Flush with electronic cleaner spray. reconnect and try again. If it isn't working, completely, soak the cluster with electronic cleaner through every hole/crack you can find. Operate all the switches a few times while the cleaner is still wet (it dries very quickly). Flush again, drain, and leave overnight in a warm, dry place. This will clean the contacts, but leave the grease on the rockers in place. Connect and give it a try. You can disassemble the cluster and clean manually, but it is very tedious (many very small parts, most are spring loaded), and there is a high risk of breaking internal (non replaceable) parts. I have about a 50/50 success rate with the brittle plastic 10+ years old switches. Replace grease with synthetic dielectric grease (tune up grease). If you find burned contacts that won't clean up (or are burned through), you'll have to fabricate. I use parts from cannibalized old appliances, radios, and toys.

[CedarGrove]

I have to spray my switches with the electronic cleaner stuff every 6 months or so. I know they need to come out and be cleaned/replaced, but a shot of that stuff keeps me going. Try simply spraying them in place before you go too deep.

Lewis

[aquaman0001]

Thanks for the input guys. Hopefully this will do and save me $100. Will I need to pull the inside door panel off to access the switch?

A

[Robyn]

OK reread the post and you need to try this FIRST
Replace the power window circuit breaker in the fuse panel. The windows are on a circuit breaker and not a fuse. HEAT and time can cause the breakers to open when they should not.

Try this first and then read more of what I have here.
__________________________________________________ ___________________________
The way the window circuits are wired requires that all the contacts are working correctly, but not all the windows should fail at once due to a bad switch.

If for example the master switch is not making contact when its in the neutral position, the individual switch for the particular window in question will not opperate the window.

When the master for any window (drivers panel) is in neutral, the ground is routed back through to the main ground buss under the dash.

There are no "Door grounds" and all the circuits ground back through the master switch.
The BLACK wire/s in the switch harness that leads out of the door are GROUND #150
The Pink wire is the hot lead (12V)
When all the switches are in the neutral position, both motor leads are grounded all the way back through the master switch and to the BUSS BAR.

Once a switch is toggled the power is then routed to either the up or down side of the motor and what was a grounded lead becomes a 12V feed. Reversing the side that has the power/ground reverses the motor.

If for example one lead on a particular switch was not connected at the individual switch the master might only be able to run the window down or maybe only up.

The MASTER switch always grounds both motor leads when its in the neutral position.
This allows the single window switches to switch the ground/power between the two lines and run the window up or down.

If none of the windows will work then the issue could be either the master ground or a power feed.

The possibility of all the contacts being bad are remote.

Yank the door panel and check to see if you have 12V at the large pink wire when the key is on, if not the issue is not the switch



Good luck

Missy

[aquaman0001]

Thanks for the reply Missy. Would you please elaborate on what the master ground is?

Thank you,
A