QuestionROLAND...THANKS FOR THE REPLY. REGARDING THE BLOWER MOTOR PROBLEM...IT IS AUTO CONTROL WITH DIGITAL READOUT. THE MORE I READ YOUR RESPONSE IT MADE ME WONDER IF EVERYTHING GOT WET UNDERNEATH. WE HAD A HUGE SNOW STORM AND THINGS GOT SNOW PACKED UNDER HIS CAR THEN WE HAD A HUGE MELT WITHIN A DAY...AND BEING A TEENAGE, HE PROBABLY WENT THRU WATER AT FULL SPEED AND GOT EVERYTHING WET. I APPRECIATE ALL YOUR HELP. LET ME KNOW ABOUT THE FAN BLOWER.
THANKS AGAIN
CINDY
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-----Question-----
My son has a 99 Chrysler LHS. We've had mysterious things going wrong off and on. First, his battery was going dead non-stop, so he got the lecture about leaving things on. It still continued to go dead, so we replaced it with a new one. (The replaced battery worked fine in my Grand Caravan)Then the power seats and windows quit working. Now, the battery went dead, couldn't charge it, couldn't get the car to turn over. Finally got the battery to charge, getting a turn over but now the wipers and fan blower won't shut off...even when you shut them off. The car won't stay running (but we think we've figured that out with the relay switches). Any ideas on the wipers, fan blower, power windows and power seats? All of the fuses are good.
Thanks! Cindy
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Hi Cindy,
I am working from the '98 wiring diagrams for the LH series cars, which I hope is the same for your '99.
The Power seats require the function of a circuit breaker #1, and the power windows circuit breaker #2 in the junction block under the dash. These are the only 2 circuit breaker and they are next to the 23 fuses, positioned between 2 plugs. So try resetting those circuit breakers to see if you get function. If not, then I would look at the ground wire which is needed for both those systems. It is located under the driver's seat, about the mid-line of the seat, and is attached by a bolt to the back side of a structural member that runs crosswise. If that wire were loose it would also defeat both systems.
The blower motor needs a little more analysis, but can you tell me if the system has a conventional control or an automatic temperature control with a digital readout?
The wipers are powered by a relay in the power distribution center box under the hood (#6). If you pulled that relay it should defeat the wipers. Why it is being activated and not controlled by the switch is to be determined. It could either be the control switch itself, or it could be a short or loose plug in the body control module which is attached to the junction block under the dash (essentially it is back half of that combined module and it has 4 plugs on the rear of the module). See if any of those plugs are loose, or possibly if water could have leaked down onto the plugs from the edge of the windshield above it. Such water intrusion can cause a variety of gremlins with body systems. Sometimes the leakage occurs in a car wash.
This is a starting set of suggestions, so I expect that you will want to write back with a progress report, which I will welcome.
Roland
AnswerHi Cindy,
Thanks for that clarification. The blower motor's power module is fed with 14 different voltage levels and with an off signal from the body computer (which is under the dash on the driver's side and is the back half of the fuse block at that location). Now either the body computer is not sending the signals to the power module or the power module has failed in some "run" position. The power module is on the lower right side of the HVAC air distribution box under the dash midline of the body. Remove the underdash pad on the right side to get a better view. By sound or vibration you should find the blower motor and it two wires which are plugged into the power module nearby. That power module can be removed and replaced with a new one. But check out its price first. I suspect though that it is much less expensive than the body module (I hear $900) so it would be worth trying that. There is a red/light green wire from the power module to pin 6 of the 24-pin black plug on the body control module (this would be on the back side of the fuse box) You could test that wire from the power module to the body module for whether it is patent using an ohmmeter or a continuity tester. Also the wire passes thru an 8-pin disconect located to the left of the HVAC housing which you could trace by following the wire to see if it might have been disconnected by someone's foot kicking the wires on either side and thus dislodging the two halves. If that all checks out, then my inclination would be to buy a new blower power module to see if you can regain control of the blower motor.
Roland
