Page 573 of 4284

Symptom List:
FRONT AND REAR BLOWER OUTPUT 1 SHORT TO BATT
FRONT AND REAR BLOWER OUTPUT 2 SHORT TO BATT
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be FRONT AND REAR BLOWER
OUTPUT 1 SHORT TO BATT.
When Monitored and Set Condition:
FRONT AND REAR BLOWER OUTPUT 1 SHORT TO BATT
When Monitored: With the ignition on.
Set Condition: The FCM detects excessive current when attempting to close the Front/
Rear Blower Motor Relays.
FRONT AND REAR BLOWER OUTPUT 2 SHORT TO BATT
When Monitored: With the ignition on.
Set Condition: The FCM detects excessive current when attempting to close the Front/
Rear Blower Motor Relays.
POSSIBLE CAUSES
CHECK DTCS
FRONT BLOWER MOTOR RELAY SHORTED
REAR BLOWER MOTOR RELAY SHORTED
FRONT/REAR BLOWER MOTOR RELAY CONTROL CIRCUIT SHORTED TO BATTERY
FRONT CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
NOTE: If neither DTC will reset or is active, refer to the wiring diagrams
located in the service information to help isolate a possible intermittent
condition.
With the DRB, read the FCM DTC's.
Are both of these DTCs set?All
Ye s®Go To 2
No®Replace the Front Control Module (FCM) in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
544
HEATING & A/C
Page 574 of 4284

TEST ACTION APPLICABILITY
2 Turn the ignition off.
Install a substitute relay in place of the existing Front Blower Motor Relay.
With the DRB, erase DTCs.
Turn the ignition on.
With the DRB, read DTCs.
Did these DTCs reset?All
Yes, equipped with rear blower motor
Go To 3
Yes, not equipped with rear blower motor
Go To 4
No®Replace the original Front Blower Motor Relay.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Install a substitute relay in place of the existing Rear Blower Motor Relay.
With the DRB, erase DTCs.
Turn the ignition on.
With the DRB, read DTCs.
Did these DTCs reset?All
Ye s®Go To 4
No®Replace the original Rear Blower Motor Relay.
Perform BODY VERIFICATION TEST - VER 1.
4 Turn the ignition off.
Remove the Front Control Module from the IPM.
Remove the Front Blower Motor Relay and the Rear Blower Motor Relay, if equipped,
from the IPM.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Front Blower Motor Relay
connector cavity 85.
Is the test light illuminated?All
Ye s®Replace the Intelligent Power Module (IPM) in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Front Control Module (FCM) in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
545
HEATING & A/C
FRONT AND REAR BLOWER OUTPUT 1 SHORT TO BATT ÐContinued
Page 589 of 4284
TEST ACTION APPLICABILITY
4 Turn the ignition on.
With the DRBIIIt, erase HVAC DTCs.
Cycle the ignition switch and wait approximately 1 minute.
With the DRBIIIt, read HVAC DTC's.
Did this DTC reset?All
Ye s®Replace the A/C - Heater Control Module in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
560
HEATING & A/C
TX FAILURE (ACTIVE) - MANUAL A/C ÐContinued
Page 671 of 4284

Symptom:
BCM MESSAGE NOT RECEIVED
When Monitored and Set Condition:
BCM MESSAGE NOT RECEIVED
When Monitored: Continuously when the PCI bus is active.
Set Condition: If the Memory Seat Mirror Module does receive this Bus message from the
BCM. Code will remain for 50 ignition cycles.
POSSIBLE CAUSES
BCM RESPONSE
STORED CODE/PCI BUS COMMUNICATION PROBLEMS
MEMORY SEAT MIRROR MODULE
INTERMITTENT PROBLEM
TEST ACTION APPLICABILITY
1 Turn ignition on.
With the DRBIIItselect Body Control Module.
Is there a response from the Body Control Module?All
Ye s®Go To 2
No®Refer to symptom *NO RESPONSE FROM BODY CONTROL
MODULE in the COMMUNICATION category
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
2 With the DRBIIIt, erase the DTC from Memory Seat Mirror Module.
Turn the ignition switch to the Off position then start the engine and let run for one
minute.
Now be sure that there is still communication with the Body Control module, if not
repair as necessary.
With the DRB check for the same DTC to reset in the MSMM.
Did the same DTC reset?All
Ye s®Go To 3
No®Test complete.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
3NOTE: Visually inspect the related wiring harness including the PCI bus
wire. Look for any chafed, pierced, pinched, or partially broken wires.
Note: Visually inspect the related wiring harness connectors. Look for
broken, bent, pushed out, or corroded terminals.
Note: Refer to any technical service bulletins that may apply.
Were any problems found?All
No®Replace the Memory Seat Mirror Module.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
Ye s®Repair as necessary.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
642
MEMORY SEAT
Page 672 of 4284

Symptom:
CHARGING VOLTAGE HIGH MESSAGE
When Monitored and Set Condition:
CHARGING VOLTAGE HIGH MESSAGE
When Monitored: During cranking or with the engine running.
Set Condition: When the Memory Seat Mirror Module receives three high charging
system voltage messages above 15.94 volts over the PCI Bus. Code will remain for 50
ignition cycles.
POSSIBLE CAUSES
PCM TROUBLE CODES
STORED CODE COMMUNICATION PROBLEMS
MEMORY SEAT MIRROR MODULE
INTERMITTENT PROBLEM
TEST ACTION APPLICABILITY
1 Turn ignition on.
With the DRBIIItread Engine DTCs.
Is the DTC P1594 Charging System Voltage Too High set in the Power Control
Module?All
Ye s®Refer to symptom *P1594-CHARGING SYSTEM VOLTAGE TOO
HIGH in the CHARGING category
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
No®Go To 2
2 With the DRBIIIt, erase the DTC from Memory Seat Mirror Module.
Turn the ignition switch to the Off position then start the engine and let run for one
minute.
With the DRB check for the same DTC to reset in the MSMM.
Did the same DTC reset?All
Ye s®Go To 3
No®Test complete.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
3Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wiring harness connectors. Look for
broken, bent, pushed out, or corroded terminals.
Note: Refer to any technical service bulletins that may apply.
Were any problems found?All
No®Replace the Memory Seat Mirror Module.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
Ye s®Repair as necessary.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
643
MEMORY SEAT
Page 673 of 4284

Symptom:
CHARGING VOLTAGE LOW MESSAGE
When Monitored and Set Condition:
CHARGING VOLTAGE LOW MESSAGE
When Monitored: During cranking or with the engine running.
Set Condition: When the Memory Seat Mirror Module receives three low charging system
voltage messages below 9 volts over the PCI Bus. Code will remain for 50 ignition cycles.
POSSIBLE CAUSES
PCM TROUBLE CODES
STORED CODE COMMUNICATION PROBLEMS
MEMORY SEAT MIRROR MODULE
INTERMITTENT PROBLEM
TEST ACTION APPLICABILITY
1 Turn ignition on.
With the DRBIIItread Engine DTCs.
Is the DTC P1682 Charging System Voltage Too Low set in the Power Control
Module?All
Ye s®Refer to symptom *P1682-CHARGING SYSTEM VOLTAGE TOO
LOW in the CHARGING category
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
No®Go To 2
2 With the DRBIIIt, erase the DTC from Memory Seat Mirror Module.
Turn the ignition switch to the Off position then start the engine and let run for one
minute.
With the DRB check for the same DTC to reset in the MSMM.
Did the same DTC reset?All
Ye s®Go To 3
No®Test complete.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
3Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wiring harness connectors. Look for
broken, bent, pushed out, or corroded terminals.
Note: Refer to any technical service bulletins that may apply.
Were any problems found?All
No®Replace the Memory Seat Mirror Module.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
Ye s®Repair as necessary.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
644
MEMORY SEAT
Page 745 of 4284

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Install a substitute CMTC/EVIC Module in place of the original module.
With the DRBIIIt, erase DTCs.
Turn the ignition on.
Cycle the ignition on and off, leaving the ignition in the on position for at least 15
seconds each time.
With the DRBIIIt, read DTCs.
Did the DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the CMTC/EVIC Module.
Perform BODY VERIFICATION TEST - VER 1.
4WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
716
OVERHEAD CONSOLE
OTIS MODULE MESSAGE MISMATCH ÐContinued
Page 747 of 4284

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Install a substitute CMTC/EVIC Module in place of the original module.
With the DRBIIIt, erase DTCs.
Turn the ignition on.
Cycle the ignition on and off, leaving the ignition in the on position for at least 15
seconds each time.
With the DRBIIIt, read DTCs.
Did the DTC reset?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the CMTC/EVIC Module.
Perform BODY VERIFICATION TEST - VER 1.
4WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
718
OVERHEAD CONSOLE
OTIS MODULE MESSAGE MISMATCH (DIESEL) ÐContinued