No high speed on fan

1995 CHEVROLET SUBURBAN

100,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC

TSHACKELFORD

MEMBER
1 POST

I have a 1995 Chevrolet Suburban that the a/c fan speed works on every position except high. I have replaced the resistor and the fan speed switch. Neither of those things fixed the problem. With the connector off the blower motor and a test light attached, power is present in all positions except high. When switched to the high speed position power is not present in the lead. Please advise. Thank you so much for any direction you might offer me.

May 25, 2014 at 8:14 PM

KASEKENNY

✓ASE Certified Mechanic
18,907 POSTS

More than likely you have an issue with the high blower relay.

This system has a separate relay just for high speed so if all speeds are working except for high then the relay is likely the issue.

So, we need to remove the relay and jump it to see if the high-speed fan comes on.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

I am attaching the wiring diagram that will help with doing this.

Please run through this and let me know what questions you have.

Thanks

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Professional Diagram for 2CarPros Members
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Jun 1, 2022 at 8:05 PM

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