2006 MERCEDES-BENZ SPRINTER air condition

Symptom:
DOSING PUMP OPEN
When Monitored and Set Condition:
DOSING PUMP OPEN
When Monitored: With the ignition on.
Set Condition: This DTC will set if the heater's control unit detects abnormally high
voltage on the Dosing Pump control circuit.
POSSIBLE CAUSES
DOSING PUMP CONTROL CIRCUIT SHORTED HIGH
DOSING PUMP
DOSING PUMP CONTROL CIRCUIT OPEN
GROUND CIRCUIT OPEN
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
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.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY
THE HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST
PRIOR TO PERFORMING ANY OTHER TEST FOR THE RESULT TO BE
VALID.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater or Heater Booster harness connector.
Turn the ignition on.
Measure the voltage between the Dosing Pump Control circuit and ground.
Is the voltage above 0.2 volts?All
Ye s!Repair the Dosing Pump Control circuit for a short to voltage.
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 2
78
CABIN HEATER

Symptom:
FLAME DETECT PRIOR TO COMBUST
When Monitored and Set Condition:
FLAME DETECT PRIOR TO COMBUST
When Monitored: During heater start up.
Set Condition: This DTC will set if the Flame Sensor's resistance is not within the
expected parameters.
POSSIBLE CAUSES
HEATER'S AIR INTAKE/EXHAUST RESTRICTED
FLAME SENSOR
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.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY
THE HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST
PRIOR TO PERFORMING ANY OTHER TEST FOR THE RESULT TO BE
VALID.
Turn the ignition off.
Inspect the heater's air intake pipe and exhaust pipe for restrictions and obstruc-
tions.
Is the heater's air intake pipe and exhaust pipe Ok?All
Ye s!Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
No!Repair the heater's air intake/exhaust as necessary in accordance
with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
87
CABIN HEATER

Symptom List:
FLAME OUT
NO START
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be FLAME OUT.
When Monitored and Set Condition:
FLAME OUT
When Monitored: After heater activation and during subsequent attempts to start the
heater.
Set Condition: This DTC will set if the Flame Sensor's resistance is not within the
expected parameters.
NO START
When Monitored: After heater activation.
Set Condition: This DTC will set if the Flame Sensor's resistance is not within the
expected parameters 340 seconds after activation.
POSSIBLE CAUSES
LOW FUEL LEVEL IN VEHICLE'S FUEL TANK
HEATER'S FUEL LINE RESTRICTED/LEAKING/DAMAGED
DOSING PUMP
HEATER'S AIR INTAKE/EXHAUST RESTRICTED
CABIN HEATER ASSEMBLY OR HEATER BOOSTER ASSEMBLY
88
CABIN HEATER

Symptom:
OVER VOLTAGE
When Monitored and Set Condition:
OVER VOLTAGE
When Monitored: With the engine running.
Set Condition: This DTC will set if the heater's power supply exceed 15.9 volts for longer
than 20 seconds.
POSSIBLE CAUSES
VEHICLE'S CHARGING SYSTEM OVERCHARGING
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
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.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY THE
HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST PRIOR TO
PERFORMING ANY OTHER TEST FOR THE RESULT TO BE VALID.
Check the vehicle's charging system for proper operation in accordance with the
Service Information.
Is the vehicle's charging system operating properly?All
Ye s!Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
No!Repair the vehicle's charging system in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
96
CABIN HEATER

Symptom List:
OVERHEATING SENSOR OPEN
OVERHEATING SENSOR SHORTED
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be OVERHEATING SENSOR OPEN.
When Monitored and Set Condition:
OVERHEATING SENSOR OPEN
When Monitored: During heater activation and operation.
Set Condition: This DTC will set if the Overheating Sensor's resistance is not within the
expected parameters.
OVERHEATING SENSOR SHORTED
When Monitored: During heater activation and operation.
Set Condition: This DTC will set if the Overheating Sensor's resistance is not within the
expected parameters.
POSSIBLE CAUSES
OVERHEATING SENSOR
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.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY
THE HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST
PRIOR TO PERFORMING ANY OTHER TEST FOR THE RESULT TO BE
VALID.
Turn the ignition off.
View repairAll
Repair
Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
97
CABIN HEATER

Symptom List:
TEMP SENSOR OPEN
TEMP SENSOR SHORTED
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be TEMP SENSOR OPEN.
When Monitored and Set Condition:
TEMP SENSOR OPEN
When Monitored: During heater activation and operation.
Set Condition: This DTC will set if the Temperature Sensor's resistance is not within the
expected parameters.
TEMP SENSOR SHORTED
When Monitored: During heater activation and operation.
Set Condition: This DTC will set if the Temperature Sensor's resistance is not within the
expected parameters.
POSSIBLE CAUSES
TEMPERATURE SENSOR
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.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY
THE HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST
PRIOR TO PERFORMING ANY OTHER TEST FOR THE RESULT TO BE
VALID.
Turn the ignition off.
View repairAll
Repair
Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
98
CABIN HEATER

Symptom:
UNDER VOLTAGE
When Monitored and Set Condition:
UNDER VOLTAGE
When Monitored: With the engine running.
Set Condition: This DTC will set if the heater's power supply voltage drops below 10.2
volts for longer than 20 seconds.
POSSIBLE CAUSES
VEHICLE'S BATTERY SYSTEM
VEHICLE'S CHARGING SYSTEM NOT OPERATING PROPERLY
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
FUSED B+ CIRCUIT HIGH RESISTANCE
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
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.
Inspect the vehicle's battery terminals, cable terminals, and cables for corrosion and
damage in accordance with the Service Information.
Test the vehicle's battery in accordance with the Service Information.
Is the vehicle's battery system Ok?All
Ye s!Go To 2
No!Clean/repair the vehicle's battery system in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
2WARNING: 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.
Check the vehicle's charging system for proper operation in accordance with the
Service Information.
Is the vehicle's charging system operating properly?All
Ye s!Go To 3
No!Repair the vehicle's charging system in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
99
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