Mechanics

REPAIR QUESTION BLOWER MOTOR RUNS CONSTSNTLY

1999 SAAB 9-3

Heater problem
1999 Saab 9-3 repair Question 4 cyl Front Wheel Drive Manual 61000 miles

I have a 99 saab 9-3se with automatic climate control. The blower motor runs all the time so I had to pull the fuse to stop the motor from running. I replaced the resistor on the motor and it still continues to run so I guess I have to replace the ACC module. The part is mounted on the evaporator according to the su[[lier, but where is the evaporator located and what is the easiest way to get to the evaporator to replace the acc module
AD
Avatar
Tom carey
April 25, 2010.



Hello .. thanks for the donation .. much appreciated

I would check for fault codes before replacing this expensive control module.. it could be a fault on the speed control unit ?

RETRIEVING DIAGNOSTIC TROUBLE CODES
During ACC control module calibration any stored and/or detected DTCs will be displayed in place of temperature. A number from 0-23 will be displayed for approximately 3 seconds each. Fan speed bars are used to indicate the number of DTCs stored. A maximum of 6 DTCs can be stored at any time. See ACC CONTROL MODULE DTCs.
Connect Saab Tech 2 or OBD-II compliant scan tool to Data Link Connector (DLC). DLC is located under instrument panel, below steering column. Turn ignition on. Following scan tool manufacturer's instructions, read and note DTCs. See ACC CONTROL MODULE DTCs and DICE CONTROL MODULE DTCs tables.
Because a functional problem in one system can be caused from a problem in another system it is important to read DTCs from all vehicle systems. Compare DTCs with customer complaint. DTC that most closely corresponds with customer complaint is probably caused by primary malfunction.

CONTROL MODULES
Manufacturer has found many control modules that have been replaced were not the cause of the problem and replacement of the control module did not correct the problem. Upon examination, these control modules were found to be free of defects. Before replacing a suspect control module, preform the following:
Before replacing ACC control module, ensure that all user-programming has been cleared. See ACC CONTROL MODULE PROGRAMMING under PROGRAMMING.

DTC B2425: FAN BLOWER MOTOR CONTROL VOLTAGE
Fault Symptoms
Fan blower motor cannot be operated from ACC control panel.
Fault Conditions
A DTC will set if a short to ground or battery voltage is detected.
Diagnostic Procedure
Disconnect fan blower motor control module 8-pin connector located on right side of climate control unit. See Fig. 2. Measure voltage between ground and fan blower motor control module 8-pin connector terminal No. 8 (Gray/Red wire). Turn ignition on. Using fan blower motor speed control buttons on ACC control panel, increase blower motor speed in steps. If voltage is 0.0-5.0 volts in short steps from minimum to maximum blower motor speed, replace blower motor control module. If voltage is not as specified, repair open or short in Gray/Red wire between fan blower motor control module and ACC control module 39-pin connector terminal No. 14. See Fig. 4. See WIRING DIAGRAMS. When repairs are completed, go to next step.
Using scan tool, clear all DTCs from all systems. Recheck A/C system operation for original complaint. If A/C system is operating properly and no DTC has been detected, repair is complete. If a DTC has been detected, a control module may need to be replaced. See CONTROL MODULES under TESTING.

FAN BLOWER MOTOR SPEED CONTROL UNIT
Removal & Installation
NOTE:DO NOT use aluminum spacer supplied with fan blower motor speed control unit.

Remove glove box. Remove trim panel from right side of center console. Remove floor air duct. Remove fan speed control unit protective cover. Remove fan speed control unit retaining screws and control unit. See Fig. 2. Disconnect wiring harness from unit.
To install, reverse removal procedure. Remove old silicon paste from control module contact surface on climate control unit. Apply a thin coating of Silicon Paste (30 07 895) to fan speed control unit mounting surface. Install fan speed control unit ensuring that both sleeves are inserted into climate control unit holes. Calibrate ACC control module. See ACC CONTROL MODULE CALIBRATION under PROGRAMMING.

ACC Control Module..Under radio.


http://www.2carpros.com/forum/automotive_pictures/266999_saab_8.jpg



Removal & Installation
Carefully pry out push buttons located directly below the ACC control module. Carefully press out ACC control module from behind. Disconnect wiring harness from ACC control module. To install, reverse removal procedure. Calibrate ACC control module. See ACC CONTROL MODULE CALIBRATION under PROGRAMMING.

Hope this helps


http://www.2carpros.com/forum/automotive_pictures/266999_AAA2_1136.png

AD

Dave H
Apr 25, 2010.
To dave h I forgot to say in my first question that I tried to recalibrate the acc contrl module by pressing the auto and the off buttons at the same time. I get an error code #02 and one bar on the fan sppeed indicator. This should norrow your answer a little. The acc control module that mounts on the evaporator according to the parts info is also the heater control, a/c fan speed control, and a/c fan resister. That why I thought replaceing this part would cover just about every thing

Tiny
Tom carey
Apr 27, 2010.
Sorry for the delay in replying.

Fault code 02/DTC 1350: CABIN TEMPERATURE SENSOR
NOTE: DTC will be cleared after ignition has been turned on 20 times if no fault conditions are detected. DTC can be cleared using scan tool.

Fault Symptoms
Temperature in cabin may seem too hot or too cold in relation to selected temperature. When DTC sets, ACC control module will initially use ambient (outside) temperature as a default value when ignition is turned on. Default value used will then be a mean value of calculated temperatures at head height of front seats.
Fault Conditions
The following conditions may cause DTC to set: Open circuit or a short to battery voltage. Voltage measured at ACC control module 39-pin connector terminal No. 20 (Blue/Yellow wire) will be more than 4.9 volts.
There is a short to ground. Voltage measured at 39-pin connector terminal No. 20 (Blue/Yellow wire) is less than 0.1 volt.
If there are 5 consecutive periods without a cabin temperature sensor signal. Every 440 milliseconds ACC control module looks for a cabin temperature sensor signal.
Diagnostic Procedure
Turn ignition off. Connect scan tool to Data Link Connector (DLC) located under steering column. Using scan tool, contact ACC control module and check for DTC B2945. If DTC B2945 is not displayed, go to next step. If DTC B2945 is displayed, go to DTC B2945: SENSOR GROUND.
Locate cabin temperature sensor in instrument panel below ACC panel and disconnect 4-pin connector. Connect a test light between battery voltage and cabin temperature sensor connector terminal No. 2 (Yellow/Brown wire). See WIRING DIAGRAMS. If test light illuminates, go to next step. If test light does not illuminate, repair Yellow/Brown wire between sensor and ACC control module 39-pin connector terminal No. 39. See Fig. 4. When repairs are complete, go to step 5.
Turn ignition on. Using scan tool, contact ACC control module and read cabin temperature sensor value. If value is 4.7-5.0 volts, go to next step. If value is not 4.7-5.0 volts, repair open in Blue/Yellow wire between sensor 4-pin connector terminal No. 3 and ACC control module connector terminal No. 20. When repairs are complete, go to step 5.
Connect a jumper wire between sensor 4-pin connector terminals No. 2 (Yellow/Brown wire) and No. 3 (Blue/Yellow wire). Using scan tool, contact ACC control module and read cabin temperature sensor value. If value is zero volts, replace cabin temperature sensor. If value is not zero volts, short in Blue/Yellow wire. When repairs are complete, go to next step.
Using scan tool, clear all DTCs from all systems. Recheck A/C system operation for original complaint. If A/C system is operating properly and no DTC has been detected, repair is complete. If a DTC has been detected, a control module may need to be replaced. See CONTROL MODULES under TESTING.

Dave H
Apr 30, 2010.

AD