I have a 97 LS and my blower motor finally stopped working after sporadically working and turning off. Sometimes it would start to work again after restarting the car or the next day, but alas now its not turning on at all.

The A/C compressor cycles fines. I replaced the blower motor resistor as that seemed to be the likely culprit but it made no difference. I have taken the blower motor out of the car and briefly connected it to a +12v source and it spins up fine. I noticed no voltage going to it when it was connected in the car and the switch was on.

I would tend to look at the blower switch and blower relay next, however a "friend" who is a mechanic says the blower motor is likely the culprit and the fact it spins up with direct 12V doesn't matter. Makes no sense to me though.

Is there a good source for the blower switch other than the dealer? Or does anyone have a tip on how to proceed next?

Thanks

 

I don't get your friend's verdict either - a motor either is blown or it isn't!!!

There was a post a while back with similar sypmtoms and it was the switch assy. If yours doesn't work on any setting then I would guess that's your problem as well.

Here's a random craigslist ad for a '97 parts truck. Hope it's not a Sport since they don't say (a pet peeve of mine)

http://savannah.craigslist.org/pts/2417337881.html

Next best bet for a used part is www.msrecycling.com but they're not super cheap - usually about 50% of retail.

Best place for OEM parts (IMO) at a reasonable discount is www.mitsubishiparts.com. (Click on the OEM catalog section first.)

Hope this helps.

Ron

 

HOLD UP on my last advice - It's probably still the switch but I just looked at the wiring diagram and it might be the relay.

Should be easy to diagnose. I can send you some more info later tonight but have to go out now. In the meantime if you want to send me your e-mail address by PM I can scan and send the wiring diagram section in pdf. This all assumes that the wiring didn't change much from 97 to 99 but it's likely the same.

Ron

 

Hey Ron,

Thanks for the help, I pm'ed you my email. I think my "friend" had too many beers when he said that about the blower motor myself.

If I am looking at the correct schematic the relay is in the engine compartment. Stupid question, is there any trick to removing the relay, I've tried to pull it after loosening some clips on the side but it doesn't budge. Afraid of damaging it.

Thanks

 

Seems my problem was the blower motor relay. It had shorted and melted a contact making it difficult to remove. Replaced it and voila, have a functioning AC again. Hopefully this was a one time thing and not a problem that will short out the new relay. Hope this helps someone else down the road.

Crispy critter

 

Good fix Raul:

Thanks for the photos - could indeed be helpful to others.

Hope this is a one time occurrence. In the wiring diagram you posted I find it curious that (as opposed to my '99 full size) there is no fuse upstream of the relay. The coil side is wired directly to the ign switch! and on the contact side there is a fuseible link, not a more easily replaced fuse. Mitsu must have had a lot of confidence in that circuit design

There are only two reasons for a relay to melt that I can think of:

1) Age and pitting of the contacts eventualy builds up resistance at the contact points which leads to heating up which leads to melting even with normal current flow.

2) A short downstream of the relay causes too much current to be pulled thru the contacts and they fry due to overrated current. i.e. they act just like an expensive fuse.

Given the intermittent failure you had in the beginning, case 1 makes more sense as pitted contacts get worse over time and can be intermittent.

Another possibility is that you had or still have an intermittent short in the switch or motor. But if this was the case hopefully Mitsu deisgned the system so that the fuseible link would have melted before the relay - that's its job after all. So it's hard to see how a shorted relay could heal itself and cause an intermittent situation.

That said, you might periodically want to touch the relay after the blower has been running for some time. If it's much hotter than its neighbors you still may have an overcurrent problem that will lead to shortened relay life.

Anyway, hope it was case 1 and that your new relay lasts for many more years. If not, carry some spare relays and start looking for a good used switch assy.

 

The blower stopped working yesterday and under advisement from my mechanic friend, I cleaned the terminal contacts with some sandpaper and some compressed air to clean out any melted junk. There was some junk on the terminal that had the short.

After disconnecting the battery, I recrimped the female end terminal by sandwiching between 2 screwdrivers as the terminal was loose fitting on the relay spade. It has been working fine since. Ideally I would like to get a new terminal but not sure where or if its worth it.

You can see where the short melted part of the terminal.

 

I know this is an old post, but I just ran into something like this and wanted to share so maybe it would help someone else. My wife's Monetero had a plugged drain and was leaking water back into the passenger floorboard. Well the other day she came home and said it stopped blowing all together. I figured it was a blown fuse first, but couldn't find one that showed problems. Next I got the tester and found the plug to the blower motor. With the key on and fan turned on I got 11.9 volts to the plug but the motor wouldn't work so I assumed it was shot. Pulled the motor but just for my own sake I wanted to test it with a battery and two wires to rule out a plug problem. I had my dad hold the fan with the blades facing down (inverted from its mounted position) to make it easy to touch the terminals and bang it came right on. I again went back to the plug and checked and was still getting voltage. I was puzzled and almost gave up till I decided to see for sure that the thing was running and not just me imagining that. This time I had it turned on the side and let it run for a second. As it ran I noticed something wasn't right. I wiggled it and turned it up like it is mounted and bang it went off altogether. Turned it back with the blades down and it came back on.
I'd bet anything that the problem of melted relays came from the short inside your blower motor just like mine.
Hope this helps someone else that may be having the same problem.