2006 MERCEDES-BENZ SPRINTER ESP

Symptom:
A. HEATER PRE-TEST
POSSIBLE CAUSES
NO RESPONSE FROM CABIN HEATER MODULE OR HEATER BOOSTER MODULE
CABIN HEATER MODULE OR HEATER BOOSTER MODULE DTC(S) PRESENT
AUTOMATIC TEMPERATURE CONTROL DTC(S) PRESENT
HEATER SYSTEM COMPONENTS
TEST ACTION APPLICABILITY
1WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
Turn the ignition off and either allow the engine coolant to cool down to at least 50ÉC
(122ÉF) or cold soak the engine.
CAUTION: When using a powered exhaust ventilation system, do not attach
the exhaust ventilation hose directly to the heater's exhaust pipe. Too much
suction can prevent heater operation.
When using a powered exhaust ventilation system, affix the ventilation hose to the
heater's exhaust pipe or to the vehicle in such a manor that the end of the ventilation
hose remains approximately three inches away from the end of the exhaust pipe.
When using a non-powered exhaust ventilation system, affix the ventilation hose
directly to the heater's exhaust pipe.
Turn the ignition on.
With the DRBIIIt, attempt to communicate with the Cabin Heater Module or Heater
Booster Module and the Automatic Temperature Control Module.
Does the DRBIIItdisplay: NO RESPONSE?All
Ye s!Refer to the Communication Category for the related symptom.
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 2
69
CABIN HEATER

Symptom:
*NO RESPONSE FROM AIRBAG CONTROL MODULE
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE AIRBAG CONTROL MODULE
K-ACM CIRCUIT SHORTED TO GROUND
K-ACM CIRCUIT SHORTED TO VOLTAGE
K-ACM CIRCUIT OPEN
AIRBAG CONTROL MODULE
TEST ACTION APPLICABILITY
1WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING. FAILURE TO DO SO MAY
RESULT IN PERSONAL INJURY OR DEATH.
Disconnect the Airbag Control Module harness connector.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform __AIRBAG VERIFICATION TEST - VER 1.
No!Go To 2
2WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING. FAILURE TO DO SO MAY
RESULT IN PERSONAL INJURY OR DEATH.
Disconnect the ACM harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-ACM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the K-ACM circuit for a short to ground.
Perform __AIRBAG VERIFICATION TEST - VER 1.
No!Go To 3
3WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING. FAILURE TO DO SO MAY
RESULT IN PERSONAL INJURY OR DEATH.
Disconnect the DRBIIItfrom the DLC.
Disconnect the ACM harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ACM circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Repair the K-ACM circuit for a short to voltage.
Perform __AIRBAG VERIFICATION TEST - VER 1.
No!Go To 4
102
COMMUNICATION

TEST ACTION APPLICABILITY
4WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING. FAILURE TO DO SO MAY
RESULT IN PERSONAL INJURY OR DEATH.
Disconnect the ACM harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-ACM circuit between the ACM connector and the
DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Airbag Control Module in accordance with the Service
Information.
Perform __AIRBAG VERIFICATION TEST - VER 1.
No!Repair the K-ACM circuit for an open.
Perform __AIRBAG VERIFICATION TEST - VER 1.
103
COMMUNICATION
*NO RESPONSE FROM AIRBAG CONTROL MODULE ÐContinued

Symptom:
*NO RESPONSE FROM AUTOMATIC TEMPERATURE CONTROL
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE AUTOMATIC TEMPERATURE CONTROL
MODULE - INTERNAL SHORT TO GROUND
K-IC, ATC, HBM, CHM CIRCUIT SHORTED TO GROUND
MODULE - INTERNAL SHORT TO VOLTAGE
K-IC, ATC, HBM, CHM CIRCUIT SHORTED TO VOLTAGE
K-IC, ATC, HBM, CHM CIRCUIT OPEN
AUTOMATIC TEMPERATURE CONTROL
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Automatic Temperature Control harness connectors.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the Automatic Temperature Control harness connectors.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-IC, ATC, HBM, CHM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Go To 4
3 Turn the ignition off.
Disconnect the Automatic Temperature Control harness connectors.
Measure the resistance between ground and the K-IC, ATC, HBM, CHM circuit.
While monitoring the ohmmeter, disconnect each module (IC, HBM, CHM) one at a
time.
NOTE: The vehicle may not be equipped with all the above modules.
Is the resistance below 5.0 ohms with all the above modules disconnected?All
Ye s!Repair the K-IC, ATC, HBM, CHM circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Module, that when disconnected the short was
eliminated, in accordance with the service information.
Perform BODY VERIFICATION TEST - VER 1.
104
COMMUNICATION

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the Automatic Temperature Control harness connectors.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-IC, ATC, HBM, CHM
circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Go To 5
No!Go To 6
5 Turn the ignition off.
Disconnect the Automatic Temperature Control harness connectors.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-IC, ATC, HBM, CHM
circuit.
While monitoring the test light, disconnect each module (IC, HBM, CHM) one at a
time.
NOTE: The vehicle may not be equipped with all the above modules.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly with all the above modules disconnected?All
Ye s!Repair the K-IC, ATC, HBM, CHM circuit for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Module, that when disconnected the short was
eliminated, in accordance with the service information.
Perform BODY VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the Automatic Temperature Control harness connectors.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-IC, ATC, HBM, CHM circuit between the ATC
connector and the DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Automatic Temperature Control in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No!Repair the K-IC, ATC, HBM, CHM circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
105
COMMUNICATION
*NO RESPONSE FROM AUTOMATIC TEMPERATURE CONTROL Ð
Continued

Symptom:
*NO RESPONSE FROM CABIN HEATER MODULE
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE CABIN HEATER MODULE
MODULE - INTERNAL SHORT TO GROUND
K-IC, ATC, HBM, CHM CIRCUIT SHORTED TO GROUND
MODULE - INTERNAL SHORT TO VOLTAGE
K-IC, ATC, HBM, CHM CIRCUIT SHORTED TO VOLTAGE
K-IC, ATC, HBM, CHM CIRCUIT OPEN
CABIN HEATER MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Cabin Heater Module harness connector.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the Cabin Heater Module harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-IC, ATC, HBM, CHM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Go To 4
3 Turn the ignition off.
Disconnect the Cabin Heater Module harness connector.
Measure the resistance between ground and the K-IC, ATC, HBM, CHM circuit.
While monitoring the ohmmeter, disconnect each module (IC, ATC, HBM) one at a
time.
NOTE: The vehicle may not be equipped with all the above modules.
Is the resistance below 5.0 ohms with all the above modules disconnected?All
Ye s!Repair the K-IC, ATC, HBM, CHM circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Module, that when disconnected the short was
eliminated, in accordance with the service information.
Perform BODY VERIFICATION TEST - VER 1.
106
COMMUNICATION

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the Cabin Heater Module harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-IC, ATC, HBM, CHM
circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Go To 5
No!Go To 6
5 Turn the ignition off.
Disconnect the Cabin Heater Module harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-IC, ATC, HBM, CHM
circuit.
While monitoring the test light, disconnect each module (IC, ATC, HBM) one at a
time.
NOTE: The vehicle may not be equipped with all the above modules.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly with all the above modules disconnected?All
Ye s!Repair the K-IC, ATC, HBM, CHM circuit for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Module, that when disconnected the short was
eliminated, in accordance with the service information.
Perform BODY VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the Cabin Heater Module harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-IC, ATC, HBM, CHM circuit between the CHM
connector and the DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Cabin Heater Module in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
No!Repair the K-IC, ATC, HBM, CHM circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
107
COMMUNICATION
*NO RESPONSE FROM CABIN HEATER MODULE ÐContinued

Symptom:
*NO RESPONSE FROM CENTRAL TIMER MODULE
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE CENTRAL TIMER MODULE
SECURITY SYSTEM MODULE
K-CTM, SSM CIRCUIT SHORTED TO GROUND
SECURITY SYSTEM MODULE
K-CTM, SSM CIRCUIT SHORTED TO VOLTAGE
K-CTM, SSM CIRCUIT OPEN
CENTRAL TIMER MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Central Timer Module harness connectors.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the CTM harness connectors.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-CTM, SSM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Go To 4
3 Turn the ignition off.
Disconnect the Security System Module harness connector.
Measure the resistance between ground and the K-CTM, SSM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the K-CTM, SSM circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Security System Module in accordance with the
service information.
Perform BODY VERIFICATION TEST - VER 1.
108
COMMUNICATION