97 Sierra Blower Motor Not Working Any Speeds....help

Replaced the Blower Motor Resistor ...no FAN at any swtich setting Removed FAN and connected both terminals direct to truck battery and it spun Tested for voltage at the blower terminals and had 13.5 volts (fan
does not spin when plugged back)
So I have 13.5 volts now at the blower motor leads but FAN not turning. Fuse of course checks good (25A position #12). Is my only option left to be the dash dial swtich ?
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Is the ground connection good on that connector

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om> wrote in messageI pulled the + and - leads (blue and black respectively) off the blower itself and put a FLUKE digital meter on the leads as I turned the blower switch. I assume the black lead (smaller tabbed wire) is a direct to ground wire ? If I measure from that black lead to a ground / chassis point I should read 0 ohms ?
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On Jan 21, 7:04 am, snipped-for-privacy@gmail.com wrote:

bare a spot on the motor and run a temporary ground to the batt. neg. to see. Jerry
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Sometimes, expecially with a digital meter, it will read full voltage until it is put under load (drawing normal current), and the voltage will drop quite a bit. I would meter the hot lead while it is connected to the blower, run a seperate lead to ground from the negative side of the blower motor wiring. When I do "jumpering" like this, I use an inline fuse just in case. YMMV.

bare a spot on the motor and run a temporary ground to the batt. neg. to see. Jerry
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Ground tested good. Also ran a separate groiund wire today. Still no fan turning. I now suspect.....FAN switch or is there a RELAY somewhere ?
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Replaced dash rotary swtich ($ 29@ GMC). All good now. Strange was that all positions showed 13.5V at the motor and the last position was 0V using the old swtich.
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