The Resistor Nemesis

[-wadestock-]

Have looked at it many times but didn't realize it's a FLEX CIRCUIT BOARD...
Holly crap no wonder the freekin thing fissles out so easy.
Key to its construction and functionality also appears to be the heat sink that is intimate with the flex board. Bad process or no contact on the flex board...well then instant fusible link.

I'm going to try and get a couple of the wiz kids here to reverse engineer this and put in REAL resistors.

[-wadestock-]

There are 2 different resistors I have. One has a piece of plastic in front of the solder connections that prevents one from seeing the connections. The other one I have shows that on the one side there are actually 3 different solder connections to the flex board. 2 of them have broken off...possibly due to the current/heat generated by a sticky motor. Also, the connection BETWEEN the 2 I'm looking at also has cracked.

Now having soldered these back, the fan still doesn't come on. And I just took the fan out and checked that it's fine. I've cleaned it and it's free wheeling.

So....I guess soldering these connections back doesn't work. Perhaps the break is in the flex itself.

[mbeach]

Is there a significant difference between the 99's and the auto control units on the 00/01's?

I assume that there is, because it appears that the fan controls are integral to the auto control unit on the 00/01s.
That being the case, it's probably still the same blower motor between the two models.
The 00/01s have a power transistor paralleled with the max-high relay, everything else is in the control unit.

Good thing too- it has warmed up to 20 degrees today.
Sunday it was -38.

[-wadestock-]

It can't be the "rebuild" of the resistor.

If you hold the resistor in this manner....


X...X....X
X.........X

The Xs being the pinouts.....then the center and top left are actually soldered together on the flex cable going into the flex resistor part. Oddly enough, the first failure mode appears to have these two connections break away from the flex cable.

Then given enough time....failure mode NUMBER 2 is to have these two connections (essentially hanging in the breez soldered together) work their way apart and now you don't have your fan working on HIGH anymore.

Having very obviously soldered this together....this means the fan should have come on....

So would someone PLEASE tell me what other fuse or fusible link is in the circuit?

Also...this means an obvious "quick fix" (provided you also don't have the "other fuse problem" I have now....is to simply jump those two connections so that your fan works on HIGH.

[-wadestock-]

My VX is dead in the water until I find out where the other fusible link or resistor is....
It's a 1999 and there is no fuse in the driver side box...is there something under the hood?
What is that thing that looks like a stick that's right next to the "resistor"?????