I was being facetious in my comment about the turning on the motor comment but apparently it didn’t come across that way. When a blower motor doesn’t work, you can’t turn it on. You can turn the fan switch on, but not the motor. If a light bulb doesn’t light and you’re trying to help someone diagnose it, you wouldn’t tell them to “turn the light on”, you’d ask them to “turn the switch on”. That was my point and apparently not a very good one.
I also didn’t want to be mean and call you out on your original post where you yelled at the OP (that’s what CAPS are). Your original post told the OP to “measure the voltage at the plug WHILE TURNING THE MOTOR ON AT ITS VARIOUS SPEEDS.”. Did you read the OP’s original post? They already did that:
If there’s no ground, there’s no voltage either. If you supply ground with your meter/test light and read voltage, then you know the motor is getting power. If you then measure across the pins on the connector and have no voltage, the issue is on the ground side. It depends on how the ground is supplied. When I was a tech, I helped several fellow techs that had misdiagnosed an issue because they did exactly what Dave did - they supplied ground with their test light/meter and thought the motor was getting power but the issue was on the ground side of the circuit.
Yeah it seems that a lot of people seem to think that a 2 terminal blower motor still uses case ground to chassis like the older 1 terminal ones did, and when you don’t use the same ground as the blower motor does, it can get you in trouble… But yeah if I had of just taken 30 seconds and double checked the blower motor (straight wired it) 1st it would have been a red flag moment and I would have checked the BM ground next instead of after the oops moment when I traced it back to that ground sided fuse (circuit breaker) box… Like I said, I knew better, just got lazy… lol
I used to work for a rotary compressor manufacturer that played cops and robbers between the operating group and quality control. Some of the foremen didn’t understand the operations and wouldn’t use test tools to fix the issues. I was a QA engineer in the machine shop and discovered solutions through testing that operations and manufacturing engineering were unfamiliar with. My tests showed what the problems were. None of them understood the chemical systems and I was continually fixing the problems they created there. I learned a lot in a short time period because they were so bad at what they did.
That’s for sure. It makes me feel like I’m not the only bonehead in the room. There’s also something very satisfying about making a mistake, learning from it, then being able to admit it to others so they don’t feel the need to be perfect all the time. It’s disarming. I’m not saying one should be lazy about not doing things properly, I’m just saying we all make mistakes and there’s nothing worse than working around a bunch of guys who can’t admit their mistakes, or ask for help, or worst, make you feel like a plonker for making a mistake.
I’m having a issue with my heat/ac , the blower motor isn’t working , I have everything removed , the resistor as well I’m not getting 12v at the 5 pin connector , but the fuse/relay is good. I just need a second set of eyes I’ve got 3-4v at the red wire on the 5 pin connector with the resistor unplugged and I’m supposed to get 12v, the fuse and relay are good as I’ve swapped them with working ones. Blower motor still won’t turn on. In the #35 fuse socket which is labeled BATT #4 that’s the blower motor fuse with it unplugged I’ve got 12v on one metal tabs and 0v on the other , going to give the 0v tab directly 12v from the battery with a jumper wire this morning and see it it turns on. I’m running in circles any input would be appreciated even if you can stop by and maybe help me for a quick second that would be great I could toss you something. Trying to get this heat and ac working , it was only blowing through the defrost vents so I replaced the blend door actuators and still nothing out the vents then I pulled the blower motor out and it’s not even spinning at all. But I bench tested it and gave it 12 v directly and it spins so I’m pretty sure it’s not the motor itself, the resistor does look corded alittle but no matter what I still should be getting 12v at the red wire (5pin connecter) and I’m not getting that . I’ve got 3-4v
ive check the jbox fuses and all check out good i even swapped them, as well as the relays. No melted connectors they look great, when i test the red wire that connects to the resistor in the car i get 4.2v nothing more, i only get 12v on one metal tab directly in the fuse junction box with the fuse removed.. The resistor does look funky with white stuff on it i’m assuming corrosion but from what ive read no matter what with the key on i still should pull 12v at the that 5 pin connector. The whole reason ive dug into this was i was only getting Ac and heat in the upper defrost vents the other vents barley blow anything they did work in the past. So i replaced the blend door actuators and nothing , then i pulled the blower motor and it doest even spin smh
any input would be appreciated even if you can stop by and maybe help me for a quick second that would be great I could toss you something. Trying to get this heat and ac working , it was only blowing through the defrost vents so I replaced the blend door actuators and still nothing out the vents then I pulled the blower motor out and it’s not even spinning at all. But I bench tested it and gave it 12 v directly and it spins so I’m pretty sure it’s not the motor itself, the resistor does look corded alittle but no matter what I still should be getting 12v at the red wire (5pin connecter) and I’m not getting that . I’ve got 3-4v