I have a 2006 Pontiac Torrent. The blower motor started working intermittently this summer. For a while, it worked on the second position. Then, it stopped working all together. At that point in time, the light on the actual knob control also stopped working. Today, using a Fluke meter, we tested the blower motor, resistor, and switch. They all work, but only test at 8 volts. The wire coming into the switch only tests at 8 volts. Is there a diode or something under the fuse box that sits on top of the battery in the engine compartment that we might be able to change? The fuses, and relays all test OK too. Please help us!!
Thank you for your question. I hope I can help. My name is XXXX XXX I will be assisting you with your question.
What color wire was the one that has 8 volts on it?
He says it was a fat yellow wire behind the blower motor control on the dash.
Was it the purple wire at the blower motor? And are you with the vehicle to do further testing?
Yes it was the purple wire. It's really dark outside to do further testing right now, could we do it tomorrow?
Yes. I would like to give you some steps for testing if you don't mind. Bear with me for just a moment.
Ok. looking at the schematic of the system the 8 volts you have on the purple and yellow wire tells me you have a bad ground. First things first use a jumper wire to ground at the blower motor purple wire and jump ground to that circuit to see if the blower operates.
Does the blower relay click when the key is turned on?
Yes, it clicks.
My men here say that they will try the ground jumper tomorrow when they have more light. If this works, are we basically making a new ground?
Ok. I have seen faulty fuse blocks causing this concern. The blower relay provides a path to ground to the blower motor. I am attaching a schematic of the system to help you out. Use a jumper wire to ground at the wire going into the HVAC control head (fat yellow wire) and see if the blower turns on. Trace that circuit to the fuse block and if no problems are found replace the fuse block. schematic is coming on next post.
Can I log back in on another computer and still see all this stuff? I am on my laptop and don't have a printer attached.
abolutely. When you are ready just go back into your account and access the question to see the schematic. Another thing you can do is when you click on the image and it pops up on the screen click on file in the upper left and then save it to your desk top for later viewing.
Cool! Thanks for all your help! We will try it tomorrow and let you know what happens
not a problem. Good luck and have a great night.
Hey Mike - are you there?
They jumped the fat yellow wire straight to the ground on the battery and still got only 8 volts. What do you think we should do next?
Still not working. Bringing it to the shop tomorrow. Thanks for trying.
sorry I missed you I was away from my computer earlier tonight and did not see your post. Before bringing it to the shop tomorrow I would run ground to the blower resistor (which should be next to the blower) terminal E the purple wire and see if the blower turns on. If it does then perform same test at the control head at each wire coming into it from the resistor (purple, yellow, light blue, and tan) which are terminals 1,2,3, and 4. let me know and I will do everything I can to help. I am around between 9 am and 1 pm EST that then will be back around 6 pm to 7 pm tomorrow.