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Rob
08-08-06, 11:36 PM
Tonight I just discovered the reoccurrence of a strange, frustrating problem with my 2000 Dodge Stratus that I first had a couple months ago, and I am seeking ideas on what might be causing it. The AC/heater fan won't work at all, except at the most powerful level. This first happened in June, and I noticed it a week after I had the battery replaced. I could blast the A/C at full chat if I wanted to, but one hot afternoon when I started the car (with the fan turned up all the way) the fan wouldn't work at all, and neither would the windows or the air bag! So I took the car in for service, and they replaced the blower motor and the resistor. It worked fine for six weeks, but when I started the car tonight I found that the problem is back. Does anybody have any ideas on what would be causing this?

Thanks in advance.
TRANSAM
08-08-06, 11:45 PM
A mechanic once told me that when you have weird electrical problems,the first thing is to check the battery connections. Since you just had the battery replaced ,maybe that's it.

I have a problem with my '75 Trans Am- the rear brakes lock up(especially one corner) way before the fronts. I'm not sure what to look at,anybody have ideas?
chop456
08-09-06, 01:55 AM
Does anybody have any ideas on what would be causing this?




2000 Dodge Stratus

You're welcome. :D
Sean O'Gorman
08-09-06, 07:23 AM
Dammit chop, I was about to post the same thing. :(
rosawendel
08-09-06, 08:29 AM
I have a problem with my '75 Trans Am- the rear brakes lock up(especially one corner) way before the fronts. I'm not sure what to look at,anybody have ideas?

when you're running down the back straight, take your right hand off of the steering wheel, and adjust the brake bias - it's the little knob just below and to the right of the steering wheel.

that's how schumacher does it, anyway...
indyfan31
08-09-06, 09:46 AM
Hey Rob, is this you? Link (http://autorepair.about.com/library/faqs/bl705e.htm)

If not, there's your answer.
RacinM3
08-09-06, 12:36 PM
Could be the new resistor has failed. But it's weird that the windows would stop working. As for the air bag, I'm assuming it fired off the air bag light, and that you didn't test it's functionality by running into the nearest wall...( :D ).

I'd check the ground connection....from the battery to the chassis of the car as well.
Rob
08-09-06, 12:39 PM
Hey Rob, is this you? Link (http://autorepair.about.com/library/faqs/bl705e.htm)

If not, there's your answer.
Thanks for that link. That's not me, but that's exactly the problem I've had. That's also what they replaced, but the fact that the replacement failed so soon makes me think there's something more. Thanks for your help.

chop: :p
Rob
08-09-06, 12:42 PM
Could be the new resistor has failed. But it's weird that the windows would stop working. As for the air bag, I'm assuming it fired off the air bag light, and that you didn't test it's functionality by running into the nearest wall...( :D ).

I'd check the ground connection....from the battery to the chassis of the car as well.
Seeing as though it felt like about 150 degrees inside the sealed-up car that day, I was worried that a real-life air bag test might have happened before I got back to work. But yes, it was the light that gave it away. Thanks for the suggestion on the ground connection. I'll mention it when I take the car back for repairs.
spinner26
08-09-06, 01:59 PM
Has anyone said 2000 Dodge Stratus YET? :D :gomer:
indyfan31
08-09-06, 02:01 PM
Thanks for that link. That's not me, but that's exactly the problem I've had. That's also what they replaced, but the fact that the replacement failed so soon makes me think there's something more. Thanks for your help.

chop: :p
Did ALL the problems come back, or just the fan control problem?

Also (and I realize it's a 2000 Stratus ;) ) but is the fan control switch strictly mechanical or do you think there's a bit of "fly-by-wire" behind the control switch?
Rob
08-09-06, 07:48 PM
Did ALL the problems come back, or just the fan control problem?

Also (and I realize it's a 2000 Stratus ;) ) but is the fan control switch strictly mechanical or do you think there's a bit of "fly-by-wire" behind the control switch?
So far, just the fan control problem, but the other problems only cropped up when I started the engine with it on full blast, and I haven't done that this time.

I'd imagine it's a strictly mechanical switch.
indyfan31
08-09-06, 11:31 PM
So far, just the fan control problem, but the other problems only cropped up when I started the engine with it on full blast, and I haven't done that this time.

I'd imagine it's a strictly mechanical switch.
Well, theoretically, the only thing between the switch and the fan is the resistor. If the resistor actually looks like this:
http://z.about.com/d/autorepair/1/0/y/X/89128470.gif
then it appears the switch simply connects the 12-volt source to different parts of the resistor, resulting in different voltage drops and different fan speeds.

The easiest thing to do first (although it may not be that easy) is to clean the contacts on that switch, then clean the contacts on the resistor connector.

If that doesn't help then the next thing to look at is the resistor itself. If they're really around $5 a piece you may want to get a couple of them. Either it failed on its own or high voltage, a spike, or heat, killed it.

It's unusual but you may also want to check the voltage at the battery while the engine is running (high idle). It should be between 14.5-15.5 volts, if it's alot higher than that then you may have a bad regulator, which means your battery will be dying soon too.

Well, that's my $.02 worth, I hope it helps and good luck.
manic mechanic
08-10-06, 12:08 AM
So far, just the fan control problem, but the other problems only cropped up when I started the engine with it on full blast, and I haven't done that this time.

I'd imagine it's a strictly mechanical switch.

I am gleaning from the thread that this Stratus does not have an electronic climate control system, (no digital display or pushbuttons for selecting fan operation, etc., right?) and that the problem is not intermittent at this point.

Chryslers are famous for ground problems (we have a few of them in the fleet), and the best thing to do is check around under the dash for any and every black wire that is screwed down to the unibody or firewall and make sure that the connections are good and clean.

Another thing to bear in mind is that Chrysler controls the alternator output through the PCM (computer) and regulates the output between 12.6 and 13.8 volts DC NO MATTER WHAT the alternator output is. If the full wave bridge (rectifier) in the system (inside the alternator) is failing, the resultant AC voltage spike can take out other components fairly quickly (hence a blower motor resistor only lasting a few weeks) so if the place that changed the battery has a scope to check the waveform of the alternator, go back to them and ask to see the pattern on your car when the technician is working on it. It should look like several small humps above the center line (no drops below the line) with even spacing. If there are parts of the wave going below the line, the IC regulatoir in the alternator is the culprit and you should change it out ASAP.

I need to add that it is very difficult to troubleshoot a problem like this without having my hands in the car and interpreting the data firsthand, but I will be glad to assist you in any way I can. the more info you can give me, the more I can narrow it down.

Feel free to ask me any questions about your car's problem that you can think of.

manic :)
Rob
08-10-06, 07:14 PM
I am gleaning from the thread that this Stratus does not have an electronic climate control system, (no digital display or pushbuttons for selecting fan operation, etc., right?) and that the problem is not intermittent at this point.
Correct, and correct.

Thanks again for your assistance, guys. I'm taking the car back to the service station Saturday morning to have them fix it again, and I'll make sure they check the ground connections and the alternator and everything else so that I don't have to do this again. Your advice is very much appreciated. :thumbup:
CARTNUT
08-10-06, 11:38 PM
I am gleaning from the thread that this Stratus does not have an electronic climate control system, (no digital display or pushbuttons for selecting fan operation, etc., right?) and that the problem is not intermittent at this point.

Chryslers are famous for ground problems (we have a few of them in the fleet), and the best thing to do is check around under the dash for any and every black wire that is screwed down to the unibody or firewall and make sure that the connections are good and clean.

Another thing to bear in mind is that Chrysler controls the alternator output through the PCM (computer) and regulates the output between 12.6 and 13.8 volts DC NO MATTER WHAT the alternator output is. If the full wave bridge (rectifier) in the system (inside the alternator) is failing, the resultant AC voltage spike can take out other components fairly quickly (hence a blower motor resistor only lasting a few weeks) so if the place that changed the battery has a scope to check the waveform of the alternator, go back to them and ask to see the pattern on your car when the technician is working on it. It should look like several small humps above the center line (no drops below the line) with even spacing. If there are parts of the wave going below the line, the IC regulatoir in the alternator is the culprit and you should change it out ASAP.

manic :)

(In my best southern shadetree mechanic accent) I betcha got sum fried wires at that there resister thingamabob!

'NUT :gomer: