heater/ac blower

[leolkfrm]

I've been reading past posts so now my problem 2003 gmc 2500hd 6.6. I have speeds 1,2,3,4, on my blower but not 5 (high). In the past low speeds go thru the resister and high is direct. Am I correct in thinking now all speeds go thru the resister relay and I need to replace it? or am I missing something?

[DmaxMaverick]

That's interesting. If only 5 doesn't work, I'd suspect the switch. 5 is non-resistored current. The resistor module could be suspect, but you'd have to test the circuits through it. The 5 circuit does pass through the resistor module, but should be unmolested.

[JohnC]

Check for a separate fuse for high.

[leolkfrm]

thankyou for the response sorry about the delay in acknowledging, blew out a motherboard, will get to it later today and post results

[leolkfrm]

Well today finally got here, its cold and I need the high speed....pulled the covers off the dash to get to relay, found the hot wire going into the relay burned thru the connecter into the relay. Monday will be shopping for a new connector and relay. checked napa online and they have a kit, sounds like a common problem.

[madmatt]

yeah it's pretty common. about a $100 for just the connector and I think another $60 for the resistor. >5 hrs labor and you'll be up and going again.

[leolkfrm]

Actually I'm seeing kits with both for about $75 in the aftermarket. figure about and hr or so to splice the 7 wires and put it back together.

[madmatt]

the prices i shot out were OE parts. Never bought'em aftermarket.

[leolkfrm]

ended up paying less then $50 from NAPA all is good now in the cold northeast

[tufcj]

Got in my 2003 yesterday, actually needed A/C here in Denver, it was 88 degrees. Only high speed on the fan worked, I suspect the resistor. Where under the dash do I find it?

Bob
tufcj

[DmaxMaverick]

Got in my 2003 yesterday, actually needed A/C here in Denver, it was 88 degrees. Only high speed on the fan worked, I suspect the resistor. Where under the dash do I find it?

Bob
tufcj

I agree, it sounds like the resistor. If you have auto climate control, hang on to your hat ($$). Remove the cover above the passenger floorboard. 3 screws (all vertical, upward, 7mm, IIRC, one hidden in a deep hole above the tranny hump). The resistor module (or fan control, if you have auto air) is held by 2 screws. If you have auto air and get the "universal" module, you'll have to splice/tap some wires. Not difficult, but not "plug 'n play".

According to the news/weather reports, you won't need A/C much lately. You'll still want the blower for the heater you'll need, though. Chilly this morning, I heard.

[tufcj]

Just the standard manual AC/heat control (left/right slider and fan control). Is it still in the same position? Yep, chilly this morning, 37 degrees when I left the house. Supposed to top out at 40 over the weekend, with hard freeze warnings overnight. Straight from summer to winter.

Bob
tufcj

[DmaxMaverick]

Yes, same location. Just different configuration and wiring. Yours will be more simple, and way less expensive.

[tufcj]

I was the resistor. The printed circuit on the OE one was almost completely delaminated. Picked an aftermarket one up at the local Advance Auto for $28 (glad to get one on a Sunday). The aftermarket one was a slightly different design, and required a little work to the attaching bracket with an X-acto knife, but not difficult. Everything plugged right in, no heat damage to the connector. I think the low speed had been out for a long time, the rest (except high) failed all at once. Back in business with all speeds working.

Bob
tufcj