2006 MERCEDES-BENZ SPRINTER engine coolant

NO COMMUNICATION WITH IC (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 Instrument Cluster.
POSSIBLE CAUSES
CHECK FOR ACTIVE AUTOMATIC TEMPERATURE CONTROL (ATC) DTCS
INTERMITTENT CONDITION
TEST ACTION APPLICABILITY
1NOTE: All of the following criteria must be met in order to successfully run
the ATC Function Test.
Place the shift lever in Park.
Turn the ignition on.
With the DRBIIIt, record and erase ATC DTC's.
Start the engine. Allow the engine to reach normal operating temperature.
Set the blower to high speed.
Press the Air Conditioning switch On.
With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the
refrigerant pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator
temperature is above 36.5ÉF (2.5ÉC), and the coolant temperature is above 158ÉF
(70ÉC).
With the DRBIIItin Automatic Temperature Control (ATC), select System Tests and
select ATC Function Test. When the ATC Function Test is complete, proceed as
follows:
With the DRBIIIt, read the active ATC DTCs.
Does the DRBIIItdisplay any DTCs?All
Ye s!Return to the Heating & A/C Symptom List and choose the
symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
No!Using the wiring diagram/schematic as a guide, inspect the
wiring and connectors related to the circuit(s) that caused the
original DTC(s) to set.
Perform BODY VERIFICATION TEST - VER 1.
131
HEATING & A/C
A/C COMPRESSOR CONTROL HIGH OR OPEN (STORED) ÐContinued

TEST ACTION APPLICABILITY
1 Verify that all of the following criteria was met when attempting to run the ATC
Function Test.
The vehicle was stationary.
The engine was running.
The air conditioning switch was On.
The ambient temperature was above 59ÉF (15ÉC).
The refrigerant pressure was between 29 and 348 PSI (2 and 24 bar).
The evaporator temperature was above 36.5ÉF (2.5ÉC).
The coolant temperature was above 158ÉF (70ÉC).
Was all criteria met when attempting to run the ATC Function Test?All
Ye s!Go To 2
No!Attempt to activate the ATC Function Test when all of the specific
operating criteria are met. If the criteria cannot be met, proceed
to Test 2 of this procedure.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition on.
With the DRBIIIt, read Automatic Temperature Control DTCs.
Does the DRBIIItdisplay any DTCs?All
Ye s!Return to the Heating & A/C symptom list and choose the
symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition on.
With the DRBIIIt, read Engine Control Module DTCs.
Does the DRBIIItdisplay any DTCs?All
Ye s!Refer to Powertrain Diagnostic information for the related symp-
tom(s).
Perform BODY VERIFICATION TEST - VER 1.
No!Refer to Service Information to diagnose the system(s) that failed
to meet the ATC Function Test operating criteria.
Perform BODY VERIFICATION TEST - VER 1.
139
HEATING & A/C
ATC FUNCTION TEST COOL FAILURE ÐContinued

Symptom:
AUX FAN RELAY CONTROL SHORTED LOW (ACTIVE)
POSSIBLE CAUSES
A/C AUXILIARY FAN RELAY
A/C AUXILIARY FAN RELAY HIGH SIDE CONTROL CIRCUIT SHORTED TO GROUND
A/C AUXILIARY FAN RELAY HIGH SIDE CONTROL CIRCUIT SHORTED TO GROUND CIRCUIT
AUTOMATIC TEMPERATURE CONTROL (ATC)
A/C AUXILIARY FAN RELAY HIGH SIDE CONTROL CKT SHORTED TO SENSOR GROUND CKT
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Install a substitute relay in place of the A/C Auxiliary Fan Relay.
NOTE: All of the following criteria must be met in order to successfully run
the ATC Function Test.
Place the shift lever in Park.
Turn the ignition on.
With the DRBIIIt, record and erase ATC DTC's.
Start the engine. Allow the engine to reach normal operating temperature.
Set the blower to high speed.
Press the Air Conditioning switch On.
With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the
refrigerant pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator
temperature is above 36.5ÉF (2.5ÉC), and the coolant temperature is above 158ÉF
(70ÉC).
With the DRBIIItin Automatic Temperature Control (ATC), select System Tests and
select ATC Function Test. When the ATC Function Test is complete, proceed as
follows:
With the DRBIIIt, read the active ATC DTCs.
Does the DRBIIItdisplay: AUX FAN RELAY CONTROL SHORTED LOW?All
Ye s!Go To 2
No!Replace the original A/C Auxiliary Fan Relay in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Remove the substitute A/C Auxiliary Fan Relay from the relay center.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between ground and the A/C Auxiliary Fan Relay High Side
Control circuit.
Is the resistance below 10K ohms?All
Ye s!Repair the A/C Auxiliary Fan Relay High Side Control circuit for
a short to ground. Reinstall the original A/C Auxiliary Fan Relay.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
142
HEATING & A/C

Symptom:
BLOWER STAGE 1 SHORTED LOW (ACTIVE)
POSSIBLE CAUSES
BLOWER MOTOR FUSE
BLOWER MOTOR
BLOWER MOTOR DRIVER CIRCUIT(S) SHORTED TO GROUND
FUSED B+ CIRCUIT SHORTED TO GROUND
BLOWER MOTOR RESISTOR BLOCK
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Remove and inspect the Blower Motor Fuse, and replace it if necessary.
NOTE: All of the following criteria must be met in order to successfully run
the ATC Function Test.
Place the shift lever in Park.
Turn the ignition on.
With the DRBIIIt, record and erase ATC DTC's.
Start the engine. Allow the engine to reach normal operating temperature.
Set the blower to high speed.
Press the Air Conditioning switch On.
With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the
refrigerant pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator
temperature is above 36.5ÉF (2.5ÉC), and the coolant temperature is above 158ÉF
(70ÉC).
With the DRBIIItin Automatic Temperature Control (ATC), select System Tests and
select ATC Function Test. When the ATC Function Test is complete, proceed as
follows:
With the DRBIIIt, read the active ATC DTCs.
Does the DRBIIItdisplay: BLOWER STAGE ONE SHORTED LOW?All
Ye s!Go To 2
No!Refer to the wiring diagrams located in the service information to
help isolate a possible intermittent short to ground condition.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Blower Motor harness connector.
Connect a fused jumper wire between Battery (+) and Blower Motor cavity 1.
Connect a jumper wire between ground and Blower Motor cavity 2.
Does the Blower Motor run at full speed?All
Ye s!Go To 3
No!Replace the Blower Motor in accordance with the Service Infor-
mation. Remove and inspect the Blower Motor Fuse, and replace
it if necessary.
Perform BODY VERIFICATION TEST - VER 1.
146
HEATING & A/C

Symptom:
CABIN HEATER CONTROL SHORTED LOW (ACTIVE)
POSSIBLE CAUSES
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
CABIN HEATER CONTROL CIRCUIT SHORTED TO GROUND
CABIN HEATER CONTROL CIRCUIT SHORTED TO GROUND CIRCUIT
CABIN HEATER CONTROL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Cabin Heater or Heater Booster harness connector.
NOTE: All of the following criteria must be met in order to successfully run
the ATC Function Test.
Place the shift lever in Park.
Turn the ignition on.
With the DRBIIIt, record and erase ATC DTC's.
Start the engine. Allow the engine to reach normal operating temperature.
Set the blower to high speed.
Press the Air Conditioning switch On.
With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the
refrigerant pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator
temperature is above 36.5ÉF (2.5ÉC), and the coolant temperature is above 158ÉF
(70ÉC).
With the DRBIIItin Automatic Temperature Control (ATC), select System Tests and
select ATC Function Test. When the ATC Function Test is complete, proceed as
follows:
With the DRBIIIt, read the active ATC DTCs.
Does the DRBIIItdisplay: CABIN HEATER CONTROL SHORTED LOW?All
Ye s!Go To 2
No!Replace the Cabin Heater Assembly or the Heater Booster assem-
bly in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Cabin Heater or Heater Booster harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between ground and the Cabin Heater Control circuit.
Is the resistance below 30k ohms?All
Ye s!Repair the Cabin Heater Control circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
150
HEATING & A/C

Symptom:
REFRIG PRESS SENSOR SHORTED LOW (ACTIVE)
POSSIBLE CAUSES
REFRIGERANT PRESSURE SENSOR
5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND
5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND CIRCUIT
5 VOLT SUPPLY CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT
REFRIGERANT PRESSURE SENSOR FEEDBACK CIRCUIT SHORTED TO GROUND
REFRIGERANT PRESSURE SENSOR FEEDBACK CIRCUIT SHORTED TO GROUND CIRCUIT
REFRIGERANT PRESSURE SENSOR FEEDBACK CIRCUIT SHORTED TO SENSOR GROUND
CIRCUIT
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Refrigerant Pressure Sensor harness connector.
NOTE: All of the following criteria must be met in order to successfully run
the ATC Function Test.
Place the shift lever in Park.
Turn the ignition on.
With the DRBIIIt, record and erase ATC DTC's.
Start the engine. Allow the engine to reach normal operating temperature.
Set the blower to high speed.
Press the Air Conditioning switch On.
With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the
refrigerant pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator
temperature is above 36.5ÉF (2.5ÉC), and the coolant temperature is above 158ÉF
(70ÉC).
With the DRBIIItin Automatic Temperature Control (ATC), select System Tests and
select ATC Function Test. When the ATC Function Test is complete, proceed as
follows:
With the DRBIIIt, read the active ATC DTCs.
Does the DRBIIItdisplay: REFRIG PRESS SENSOR SHORTED LOW?All
Ye s!Go To 2
No!Replace the Refrigerant Pressure Sensor in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between ground and the 5 Volt Supply circuit.
Is the resistance below 10k ohms?All
Ye s!Repair the 5 Volt Supply circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
173
HEATING & A/C

BODY VERIFICATION TEST - VER 1 APPLICABILITY
1. Disconnect all jumper wires and reconnect all previously disconnected components and
connectors.
2. Ensure that all accessories are turned off and the battery is fully charged.
3. NOTE: Refer to the service information for proper programming procedures if the
ABM; ACM; ATC; CTM; ECM; IC; SKREEM; SLA; or SSM was replaced.
4. If the SKREEM was replaced, program all RKE transmitters used with this vehicle.
5. NOTE: Perform the next 8 steps of this procedure if either diagnosing the
Automatic Temperature Control (ATC) system or if repairs were made to the ATC
system. All of the following criteria must be met in order to successfully run the ATC
Function Test.
6. With DRBIIIt, record and erase ATC DTCs.
7. Place the shift lever in Park.
8. Start the engine. Allow the engine to reach normal operating temperature.
9. Set the blower to high speed.
10. Press the Air Conditioning switch On.
11. With the DRBIIIt, verify that the ambient temperature is above 59ÉF (15ÉC), the refrigerant
pressure is between 29 and 348 PSI (2 and 24 bar), the evaporator temperature is above 36.5ÉF
(2.5ÉC), and the coolant temperature is above 158ÉF (70ÉC).
12. With the DRBIIItin ATC, select System Tests and select ATC Function Test. When the ATC
Function Test is complete, proceed to the next step of this procedure.
13. With the DRBIIIt, read active ATC DTCs. If any DTC is active or if the original condition
is still present, proceed to the conclusion question and answer Yes.
14. With the DRBIIIt, record and erase all DTCs from ALL modules. Start and run the engine
for 2 minutes. Operate all functions of the system that caused the original concern.
15. Turn the ignition off and wait 5 seconds. Turn the ignition on and using the DRBIIIt, read
DTCs from ALL modules.
Are any DTC's present or is the original condition still present?All
Ye s!Repair is not complete, refer to the appropriate symptom.
No!Repair is complete.
245
VERIFICATION TESTS
Verification Tests ÐContinued

HEATER VERIFICATION TEST - VER 1 APPLICABILITY
1. WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA THAT DOES
NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS VENT THE HEATER's
EXHAUST WHEN OPERATING THE HEATER. FAILURE TO FOLLOW THESE IN-
STRUCTIONS CAN RESULT IN PERSONAL INJURY OR DEATH.
2. WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PERFORMING A
COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAILURE TO FOLLOW
THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY OR DEATH.
3. NOTE: The heater's control unit will store up to five DTCs in its memory.
4. NOTE: If the heater's control unit detects a new fault in the system, one that is not
already stored in its memory, it will clear the oldest of the five stored DTCs, and it
will store the new fault's DTC.
5. NOTE: If the heater's control unit detects a reoccurrence of a stored fault, it will
overwrite that fault's DTC with the most recent occurrence.
6. Verify that the vehicle's battery is fully charged.
7. Verify that there is more than 1/8 of a tank of fuel in the vehicle's fuel tank. Add fuel, if
necessary.
8. Verify that all heater's coolant hoses and fuel lines are securely fastened to their respective
components.
9. Disconnect all jumper wires and reconnect all previously disconnected components and
connectors.
10. If a heater installation/cooling system service was performed, purge the coolant circuit of air
in accordance with the Service Information.
11. Turn the ignition on.
12. Verify that the Cabin Heater or Heater Booster is switched off.
13. Ensure that all accessories are turned off.
14. Set the blend control to the max heat position and the mode control to the floor position.
15. If a fuel system service requiring fuel to drain out of the heater's fuel line was performed,
prime the heater's Dosing Pump in accordance with the Service Information.
16. With the DRBIIIt, record and erase all DTCs from the Cabin Heater Module or Heater
Booster Module. Turn the ignition off, wait 5 seconds, then turn start the engine.
17. Allow the engine to idle.
18. 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.
19. Switch the Cabin Heater or Heater Booster on. Allow the heater to run through at least one
cycle of operation (approximately 10 minutes), and then turn the heater off.
20. With the DRBIIIt, read the Cabin Heater or Heater Booster Module's DTC.
21. Turn the engine off.
Are any DTC's present or is the original condition still present?All
Ye s!Repair is not complete, refer to the appropriate symptom.
No!Repair is complete.
246
VERIFICATION TESTS
Verification Tests ÐContinued