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Topic: 1988 XR7 Blower Resistor w ATC (Read 1691 times) previous topic - next topic

1988 XR7 Blower Resistor w ATC

The Blower on my Black Cat runs at different selected speeds (Hi, Low) but turns way to slow. I just replaced the heater core that was clogged. While I was back there I replaced the blower. The speed has not improved. I bought a resistor but can't find one to replace under the dash. All I can find is the temp sensor for the ATC. Is there a resistor? Whats next? Junk yard atc control and sensor?

1988 XR7 Blower Resistor w ATC

Reply #1 –
look at this,, your blower motor resistor assembly is behind the glove box.
if it went bad, it requires a new thermal limiter per the EVTM you can get within the diy link below.

1988 XR7 Blower Resistor w ATC

Reply #2 –
Normally people complain because it runs on high only,
i am looking at EVTM pages for something that would cause a "too slow" condition.

1988 XR7 Blower Resistor w ATC

Reply #3 –
ok,, there is a blower motor speed controller with EATC as per page 224 of the EVTM

humm, yep, its claimed that there is a blower motor controller located at the center of the EVAP case, however i cant remember ever actually seeing one yet even though i have it in my car.

your looking for a blue connector with 6 terminals, the main power terminal is a blue/light pink.
Hopefully the EVTM is correct.
IT appears the EATC controller controls singles to the "blower motor speed controller"

if you have the time, you should look for it and

1988 XR7 Blower Resistor w ATC

Reply #4 –
Thanks for the pic. The thing I pulled from that spot has a big sensor on it. It required the dash to be pulled back.

1988 XR7 Blower Resistor w ATC

Reply #5 –
You think thats my problem? Advanced Auto only had the small resistor. I may have to visit the junk yard or try to bypass for full air.

1988 XR7 Blower Resistor w ATC

Reply #6 –
pull the codes, per our diy link below my sig
Pull your codes, i did not say what i thought would be a problem, just getting the troubleshooting started.
The car will tell you what is wrong.,,not me. 
Once we know a code number, thats the best place to start and then start practical trouble shooting.

It would be nice to tell us recently what caused you to dive into this project in the first place,, just a slow motor or was there something else?

==============================================
EATC or ATC codes and troubleshooting

ATC Codes
possible of codes 1-15, code 88 is system passes test
press OFF/Auto an defrost at the same time, then press AC within 2 seconds to display the code
Press "cool" button to stop the test and exit,
The ATC will stop working while in "test mode"
01    Blend door actuator out of position.
02    Floor/Panel actuator out of position.
03    Panel/Defrost out of position.
04    Outside air/recirculation actuator out of position.
05    Blend actuator over current.
06    Floor/Panel actuator over current.
07    Panel/Defrost actuator over current.
08    Outside air/recirculation actuator over current.
09    No faults found in self-test.
10    If this appears with any other code, ignore it. If it appears alone, it's the same as code 88.
11    Clutch signal low.
12    Sensor string open (NOTE: if the interior of the car is very cold this error may appear. Try warming up the car, shut off the ignition, restart the car, and enter the self test again).
13    Sensor string shorted.
14    Control head unit worn or damaged (unit must be replaced).
15    Blower signal shorted.
88    No faults found in self-test.

Also see here for all things about your car specific to EATC >http://www.coolcats.net/help/atc.html

1988 XR7 Blower Resistor w ATC

Reply #7 –
Thanks,I will try the codes today. I started this because I had to replace the heater core. The windows were covered w moisture.

1988 XR7 Blower Resistor w ATC

Reply #8 –
It displayed "88".
 

1988 XR7 Blower Resistor w ATC

Reply #9 –
that sucks,

check the two fuses,
 it looks like the ground side of the blower motor is being controlled or managed by the controller.

there's a fuse to power the controller and there is a fuse to power the blower.
it appears that the orange wire is the conductor that is acting as ground but the controller manages this.

First check fuses
next , with a test light, see if there is power on the orange wire while the belower is running and report back.

you may have a ground problem with the circuit.