2006 MERCEDES-BENZ SPRINTER relay

TEST ACTION APPLICABILITY
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.
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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the Circulation Pump Relay from the relay center.
Measure the resistance of the Circulation Pump Relay High Side Control circuit
between the Cabin Heater harness connector and the relay center (Circulation Pump
Relay connector terminal 86).
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Repair the Circulation Pump Relay High Side Control circuit for
an open.
Perform HEATER VERIFICATION TEST - VER 1.
3WARNING: 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.
Reconnect the Cabin Heater harness connector.
Install a substitute relay in place of the Circulation Pump Relay.
Turn the ignition on.
Verify that the Cabin Heater is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
With the DRBIIIt, erase the Cabin Heater Module's DTCs.
Start the engine. Allow the engine to idle.
With the DRBIII, monitor for Cabin Heater Module DTCs while performing the
following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater on. If necessary, allow the heater to run through at least one
cycle of operation (approximately 10 minutes), and then turn the heater off.
Turn the engine off.
Does the DRBIIItdisplay: CIRC PUMP CONTROL OPEN?All
Ye s!Replace the Cabin Heater Assembly in accordance with the
Service Information. Reinstall the original Circulation Pump
Relay.
Perform HEATER VERIFICATION TEST - VER 1.
No!Replace the original Circulation Pump Relay in accordance with
the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
73
CABIN HEATER
CIRC PUMP CONTROL OPEN ÐContinued

Symptom:
CIRC PUMP CONTROL SHORTED
POSSIBLE CAUSES
CIRCULATION PUMP RELAY
CIRCULATION PUMP RELAY HIGH SIDE CONTROL CIRCUIT SHORTED TO GROUND
PUMP RELAY HIGH SIDE CONTROL CKT SHORTED TO PUMP RELAY GROUND CKT
CABIN HEATER 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.
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.
Install a substitute relay in place of the Circulation Pump Relay.
Turn the ignition on.
Verify that the Cabin Heater is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
With the DRBIIIt, erase the Cabin Heater Module's DTCs.
Start the engine. Allow the engine to idle.
With the DRBIII, monitor for Cabin Heater Module DTCs while performing the
following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater on. If necessary, allow the heater to run through at least one
cycle of operation (approximately 10 minutes), and then switch the heater off.
Turn the engine off.
Does the DRBIIItdisplay: CIRC PUMP CONTROL SHORTED?All
Ye s!Go To 2
No!Replace the original Circulation Pump Relay in accordance with
the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
74
CABIN HEATER

TEST ACTION APPLICABILITY
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.
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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the substitute Circulation Pump Relay from the relay center.
Measure the resistance between ground and the Circulation Pump Relay High Side
Control circuit.
Is the resistance below 10K ohms?All
Ye s!Repair the Circulation Pump Relay High Side Control circuit for
a short to ground. Reinstall the original Circulation Pump Relay.
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 3
3WARNING: 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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the Circulation Pump Relay from the relay center.
Measure the resistance between the Circulation Pump Relay High Side Control
circuit and the Ground circuit (Circulation Pump Relay connector terminal 86 and
85).
Is the resistance below 10K ohms?All
Ye s!Repair the Circulation Pump Relay High Side Control circuit for
a short to the Ground circuit.
Perform HEATER VERIFICATION TEST - VER 1.
No!Replace the Cabin Heater Assembly in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
75
CABIN HEATER
CIRC PUMP CONTROL SHORTED ÐContinued

Symptom:
FAN STAGE 1 RELAY CONTROL OPEN
POSSIBLE CAUSES
GROUND CIRCUIT OPEN
FAN STAGE 1 RELAY HIGH SIDE CONTROL CIRCUIT OPEN
FAN STAGE 1 RELAY
CABIN HEATER 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.
Remove the Fan Stage 1 Relay from the relay center.
Measure the resistance between ground and the Ground circuit in the relay center
(Fan Stage 1 Relay connector terminal 85).
Is the resistance below 5.0 ohms?All
Ye s!Go To 2
No!Repair the Ground circuit for an open.
Perform HEATER VERIFICATION TEST - VER 1.
83
CABIN HEATER

TEST ACTION APPLICABILITY
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.
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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the Fan Stage 1 Relay from the relay center.
Measure the resistance of the Fan Stage 1 Relay High Side Control circuit between
the Cabin Heater harness connector and the relay center (Fan Stage 1 Relay
connector terminal 86).
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Repair the Fan Stage 1 Relay High Side Control circuit for an
open.
Perform HEATER VERIFICATION TEST - VER 1.
3WARNING: 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.
Reconnect the Cabin Heater harness connector.
Install a substitute relay in place of the Fan Stage 1 Relay.
Turn the ignition on.
Verify that the Cabin Heater is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
With the DRBIIIt, erase the Cabin Heater Module's DTCs.
Start the engine. Allow the engine to idle.
With the DRBIII, monitor for Cabin Heater Module DTCs while performing the
following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater on. If necessary, allow the heater to run through at least one
cycle of operation (approximately 10 minutes), and then switch the heater off.
Turn the engine off.
Does the DRBIIItdisplay: FAN STAGE 1 RELAY CONTROL OPEN?All
Ye s!Replace the Cabin Heater Assembly in accordance with the
Service Information. Reinstall the original Fan Stage 1 Relay.
Perform HEATER VERIFICATION TEST - VER 1.
No!Replace the original Fan Stage 1 Relay in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
84
CABIN HEATER
FAN STAGE 1 RELAY CONTROL OPEN ÐContinued

Symptom:
FAN STAGE 1 RELAY CONTROL SHORTED
POSSIBLE CAUSES
FAN STAGE 1 RELAY
FAN STAGE 1 RELAY HIGH SIDE CONTROL CIRCUIT SHORTED TO GROUND
FAN STAGE 1 RELAY HIGH SIDE CONTROL CIRCUIT SHORTED TO GROUND CIRCUIT
CABIN HEATER 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.
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.
Install a substitute relay in place of the Fan Stage 1 Relay.
Turn the ignition on.
Verify that the Cabin Heater is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
With the DRBIIIt, erase the Cabin Heater Module's DTCs.
Start the engine. Allow the engine to idle.
With the DRBIII, monitor for Cabin Heater Module DTCs while performing the
following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater on. If necessary, allow the heater to run through at least one
cycle of operation (approximately 10 minutes), and then switch the heater off.
Turn the engine off.
Does the DRBIIItdisplay: FAN STAGE 1 RELAY CONTROL SHORTED?All
Ye s!Go To 2
No!Replace the original Fan Stage 1 Relay in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
85
CABIN HEATER

TEST ACTION APPLICABILITY
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.
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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the substitute Fan Stage 1 Relay from the relay center.
Measure the resistance between ground and the Fan Stage 1 Relay High Side Control
circuit.
Is the resistance below 10K ohms?All
Ye s!Repair the Fan Stage 1 Relay High Side Control circuit for a short
to ground. Reinstall the original Fan Stage 1 Relay.
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 3
3WARNING: 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.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater harness connector.
Remove the Fan Stage 1 Relay from the relay center.
Measure the resistance between the Fan Stage 1 Relay High Side Control circuit and
the Ground circuit (Fan Stage 1 Relay connector terminal 86 and 85).
Is the resistance below 10K ohms?All
Ye s!Repair the Fan Stage 1 Relay High Side Control circuit for a short
to the Ground circuit.
Perform HEATER VERIFICATION TEST - VER 1.
No!Replace the Cabin Heater Assembly in accordance with the
Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
86
CABIN HEATER
FAN STAGE 1 RELAY CONTROL SHORTED ÐContinued

Symptom List:
A/C COMPRESSOR CONTROL HIGH OR OPEN (STORED)
A/C COMPRESSOR CONTROL SHORTED LOW (STORED)
AIR OUTLET TEMP SENSOR HIGH OR OPEN (STORED)
AIR OUTLET TEMP SENSOR SHORTED LOW (STORED)
AUX FAN RELAY CONTROL HIGH OR OPEN (STORED)
AUX FAN RELAY CONTROL SHORTED LOW (STORED)
BLOWER STAGE 1 HIGH OR OPEN (STORED)
BLOWER STAGE 1 SHORTED LOW (STORED)
CABIN HEATER CONTROL HIGH OR OPEN (STORED)
CABIN HEATER CONTROL SHORTED LOW (STORED)
CIRC PUMP CONTROL HIGH OR OPEN (STORED)
CIRC PUMP CONTROL SHORTED LOW (STORED)
EVAP TEMP SENSOR HIGH OR OPEN (STORED)
EVAP TEMP SENSOR SHORTED LOW (STORED)
NO COMMUNICATION BUS (STORED)
NO COMMUNICATION WITH ECM (STORED)
NO COMMUNICATION WITH IC (STORED)
RECIRC AIR SOLENOID CONTROL HIGH OR OPEN (STORED)
RECIRC AIR SOLENOID CONTROL SHORTED LOW (STORED)
REFRIG PRESS SENSOR HIGH OR OPEN (STORED)
REFRIG PRESS SENSOR SHORTED LOW (STORED)
WATER CYCLE VALVE CONTROL HIGH OR OPEN (STORED)
WATER CYCLE VALVE CONTROL SHORTED LOW (STORED)
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be A/C COMPRESSOR CONTROL
HIGH OR OPEN (STORED).
When Monitored and Set Condition:
NO COMMUNICATION BUS (STORED)
When Monitored: With the ignition on.
Set Condition: This DTC will set if the Automatic Temperature Control (ATC) fails to
receive all module messages.
NO COMMUNICATION WITH ECM (STORED)
When Monitored: With the ignition on.
Set Condition: This DTC will set if the Automatic Temperature Control (ATC) fails to
receive all messages from the ECM.
130
HEATING & A/C