1999 Chevy Tahoe

[dlackie819]

Does the fan turn on? Did you replace it? Checked for power at the fan? What exactly isn't working properly.

Replaced all the actuators the main switch is in the dash the resistor at the top of the heating box and what's that next to it is a relay that I replaced too and still have no power to the blowers but I can run a hotline to the blower and make it work kind of hotline 20 of fuse and 20 amp switch but I still have no power coming through the switch in the dash for the blowers so I got a blockage in the system somewhere and I can't find it or I don't know how to find it schematics I look up are all for suburbans and Silverados but not my 99 Tahoe it's hard to find correct information if it's not available

 

[GMCChevy]

That helps knowing what you've already done but I wouldn't have any more suggestions for you.
Suburban is the same as Tahoe and Silverado that body style was the same also but 99 was the change over year for pickups so it needs to be for the older body style. But any info for those is the same as Tahoe.

 

[east302]

Simple system to troubleshoot. Do you have power AND ground at the blower motor? If you want a guess the connector on the back of the blower switch is known to melt. Have you had the control out?

What does the connector that plugs into the blower switch at the control panel look like? Jiggle it around and see if the blower responds.

Some years had an intermediate connector on the power line maybe 1-ft from where it connects on the blower. Those can melt as well.

 

[Eman85]

Just a troubleshooting tip for those that troubleshoot electrical problems. Something like a blower motor requires amperage so measuring voltage with a meter or test light doesn't tell the whole story of a circuit. Making a test light from a headlamp can help when you are checking a circuit that draws higher amperage. The higher amperage draw is what causes the connectors to melt over time and while you might read voltage it might not hold the connection when a higher amp draw is applied.

 

[dlackie819]

Does the fan turn on? Did you replace it? Checked for power at the fan? What exactly isn't working properly.

no power at fan

 

[Eman85]

no power at fan

Start tracing back, any power at relay? From memory relay should be behind glove box. look at the wiring diagram above and you can see which wires should have power and when.