brunder

My 6 pin wiring harness to the resistor melted on one end causing my high setting not to work. (this probably happened over time) I cleaned it up with a knife & its working for now, but I realize its a temporary bandaid. The vehicle is a 2007 with 10k miles so I don't get why its overheating. Do faulty resistors contribute to the overheating problem or is it more likely fan amperage problem? Its 115+ degrees here in the summer so I connected a manual switch to a fan mounted on front of the condensor so I could get better cooling & colder a/c at idle. For a 3 month period the switch connecting my 2nd battery wasn't working right so I was running on only 1 battery . I'm wondering if during that time running the blower on high + the auxiliary condensor fan caused the battery voltage to go down creating a higher amp draw on the resistor & more heat to the harness. What max amp draw should these blowers be at on high speed and is there a correlation between battery voltage & resistor/harness overheating?

mountainmanjoe

Always post your vehicle info please.

Your blower motor is failing. They start to short out and fry the resistors and connectors.

RoadTrip

^ This!

jfmorris

You can replace the melted blower resistor connector. Rockauto.com should have one.

My son has a 2005 Colorado that he bought from my father, and I helped him replace the blower and blower resistor recently. The resistor kit he bought online actually came with a new connector for the vehicle side - which was good because the wiring harness connector was pretty melted and burned up. And the one that was on the vehicle was was not the original, but had been spliced and crimped on too. I spoke with my dad, and the Chevy dealer back in Georgia had replaced the blower resistor and connector maybe 10 years ago. Apparently this is a problem on a lot of these vehicles, as my 1996 C1500 melted the blower wire itself, and I replaced that and the connector this year.

brunder

My 2007 Chev express is drawing 17.3 amps on the red wire when my ac blower is set to high. What is the normal range?

mountainmanjoe

(please keep all your troubleshooting together in one place, so we don't have to go hunting all over for context. I've merged your threads)


About that. 20ish amps.

However, the motors will fail intermittently. The bushings dry out and start to seize. The motor will periodically stall, causing a short, and burns out circuit components. Once it gets spinning again (like if you give it a thump) , then it will appear to draw normal current again. Repeated events like this will fry resistors and wires, melt connectors etc. over time. Then, the poor connections exacerbate the problem and problem compounds (snowballs). The lifespan of these motors is only around 10 years.

brunder

The vehicle has only around 15k miles on it and the engine hour meter looks about right for that many miles. Although I don't know if its very common these parts can fail over time from just sitting. I did have a low voltage situation last year when I found out my 4 awg stinger switch failed on the 2 batteries connected in parallel causing the 3000 watt inverter to draw from only 1 battery. I'm aware lower volts=higher amps & wondering if the high side of the harness overheated during that incident. If its possible the charred (red wire) connector had just enough connection left to keep it running on high until 9 months later when it finally quit.

mountainmanjoe

15k miles for a 17 year old vehicle ... seems a little too good to be true.

jfmorris

Sometimes vehicles like that are out there. My son in law bought my elderly neighbors 2008 GMC Denali SUV back in February after they went into a nursing home. 14,000 miles on the vehicle, and garaged its entire life, looks like it just came off the showroom floor. He paid $14,000 for it. Every possible option was on that vehicle. I would have bought it myself by my wife didn't want to drive something as big as my Silverado...

So far the only issue we've found is that the sway bar links were literally missing their bushings, and rattle. I've looked at it and think the bushings at each end of the link were missing from the factory, as they haven't even dry rotted off on my 1996 C1500, stored outside.

mountainmanjoe

I know low mileage vehicles are out there, but so are scammers. Probably more of the latter.