NO high speed blower

87GNSteve

Just another pretty face....
Joined
Jan 15, 2004
I did the tests in the GM manual and it doesn't diagnose the problem.
I tried swapping:
blower motors.
relays
switches.
I have lo, m1 and m2 fan will go high speed if jumped.
Any ideas?
 
Mine did that, too:confused:
Try the purple wire running down the firewall/wheel-well area it can get corroded at the connector (its down in the cavity of a bit) it's a direct feed to the blower motor (high), bypassing the resistor. Best bet since you're able to jump it & it works.
HTH!

D o_O
 
When I say I jumped the motor, I did not apply power directly to the motor but removed the relay and jumped main power to the Hi circuit. That led me to believe the purple wire was OK .
Flawed thinking?
 
Steve,
By "main power" are you referring to the purple wire or jumping directly from batt or other known good 12v source (including resistor/relay feed)?
The power from resistor/relay is a separate feed than the purple wire, the purple wire is a direct feed to blower motor ("high" is the normal state for the motor, the resistor/relay increases resistance, slowing blower speed)
if your getting power to "low" &" med" settings then that feed is good & blower motor is good;
the only remaining area is the (damn) purple feed wire and/or the connector down in the firewall/wheel well so you nee to physically verify its integrity & check continuity w/ a multimeter.
I guess there is a really off chance that the switch in the A/C control head unit is bad,but I would consider that a long-shot.
but I would suspect the something related to the purple wire;
my grandfather's :pompous: dying words to me were "...never... trust... a purple... wire...".
Weird, huh?:confused:

post when you figger it out?!?

Do_O
 
There is a plug that always get corroded down under the antenna area. You can usually get the fan to kick on just by wiggling the wire. The real fix is to unplug, clean the connection, put a little grease on and plug back in. But it's allot easier said than done.
 
Ok here is one for the record books.
I found the problem.
connect.jpg
 
That connector is one of the biggest failures in the wiring harness. It's buried between the inner fender well and the firewall, near the electric antenna connector (2nd. biggest failure). The rain is channeled right into that area.

You will need to replace both male and female terminals on those connectors, then saturate both halves in white lithium grease. I have been procrastinating for years, but will probably put together a repair kit for that connection. The fact that the unused wire (black) is a ground adds to the destruction of that connection; there's a constant HOT wire in the connector, causing electrolysis. HINT: Cut the black wire out of the equation.
 
So you are thinking ( Like I did)
oh, just fish down there and re-plug that baby back in.;)
So I get my flash light and look, canNOT see it.
I get my LED flash light and a tiny mirror. cannot see it.
Take off the front wheel and loosen the plastic splash guard, lay on the ground and look up, don't see it.
I go to my T type and see the connector male and female ends, right up at the top. Ok....o_O

I loosen the fender from the door hinge side and make more room.
Dont see it. Go back to the t type and trace where it comes from. The main engine harness; last stop before the bulkhead pass through.
I tape my smart phone to a paint stick, put it on video and stick the phone in the depths.
I watch the video, make 2 more and CANT SEE that connector for DOO DOO.....:wacky:
Then I pull the conduit off the main harness, and realize its not there.

Remember the song from The Zombies "Shes not there?" Well neither is the connector. Gone.
"Dont bother trying to find her, shes not there......."
How did this happen you ask? Well I happened to have bought a harness form a board member here who told me his was a super low mile, pristine unit.
I paid a fair price and it was exceptional looking when I received it, I was delighted as my old one was greasy and crusty.
But so far I had to repair a wire going into the ECM, 3 wires at the bulkhead that pulled out of the connectors, and now a cut off connector that will require me to remove the fender from a freshly painted car to repair.

So if you dont see me on here anymore my neighbors called the authorities and had me committed because of my mumbling loud rants while working on the car today....
 
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I was able to fix it without pulling the fender.
I disconnected the ECM and accessory pigtails used my trusty weed eater line and taped it to the end, I then sprayed the grommet w/ silicone removed the retainer from the firewall (not fun).
And yanked the harness up from the engine bay.
Pics show the weed eater line after the harness was pulled; and the two cut wires the red and blue. The harness was taped up like you wouldn't believe and gave no indication there were cut wires under there.
I was very fortunate to have the connector end off of another harness. I removed the terminals and wire brushed them and reinstalled with lots of dielectric grease and I eliminated the unused ground like John suggested.
To get the harness back in I just pulled on the weed eater line and fished the connectors through, and tugged on the harness the silicone spray made it easier to seat the grommet.
 

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