2006 MERCEDES-BENZ SPRINTER light

Symptom:
*NO RESPONSE FROM SENTRY KEY REMOTE ENTRY MODULE
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE SENTRY KEY REMOTE ENTRY MODULE
K-SKREEM CIRCUIT SHORTED TO GROUND
K-SKREEM CIRCUIT SHORTED TO VOLTAGE
K-SKREEM CIRCUIT OPEN
SENTRY KEY REMOTE ENTRY MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the SKREEM 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 SKREEM harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-SKREEM circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the K-SKREEM circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the SKREEM harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-SKREEM 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-SKREEM circuit for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 4
122
COMMUNICATION

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the Shifter Assembly harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ABS, Shifter Assembly
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 Controller Antilock Brake harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ABS, Shifter Assembly
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-ABS, Shifter Assembly circuit for a short to voltage.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Controller Antilock Brake in accordance with the
service information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-ABS, Shifter Assembly circuit between the Shifter
Assembly connector and the DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Shifter Assembly in accordance with the Service
Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Repair the K-ABS, Shifter Assembly circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
125
COMMUNICATION
*NO RESPONSE FROM SHIFTER ASSEMBLY ÐContinued

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the TCM harness connectors.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-TCM, RADIO 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 Radio harness connectors.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-TCM, RADIO 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-TCM, RADIO circuit for a short to voltage.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Radio in accordance with the service information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the TCM harness connectors.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-TCM, RADIO circuit between the TCM connector
and the DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Transmission Control Module in accordance with the
Service Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Repair the K-TCM, RADIO circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
127
COMMUNICATION
*NO RESPONSE FROM TRANSMISSION CONTROL MODULE ÐContinued

Symptom:
CABIN HEATER CONTROL HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
CABIN HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
CABIN HEATER CONTROL CIRCUIT OPEN
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition on.
Verify that the Cabin Heater or Heater Booster is switched off.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater or Heater Booster harness connector.
Connect a 12-volt test light between the Cabin Heater Control circuit and ground.
Turn the ignition on. The test light should operate as follows:
With the Cabin Heater or Heater Booster switched off, the test light should not
illuminate.
Press the Cabin Heater or Heater Booster switch on. The test light should illuminate
brightly.
Does the test light function as specified?All
Yes, Light Only Illuminates w/Switch On
Replace the Cabin Heater Assembly or the Heater Booster Assem-
bly in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No, Light Illuminates w/Switch Off
Go To 2
No, Light Will Not Illuminate
Go To 3
2 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Cabin Heater or Heater Booster harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Turn the ignition on.
Measure the voltage of the Cabin Heater Control circuit.
Is the voltage above 0.2 volts?All
Ye s!Repair the Cabin Heater Control circuit for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
148
HEATING & A/C

Symptom:
CIRC PUMP CONTROL HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
CIRCULATION PUMP
CIRCULATION PUMP CONTROL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
CIRCULATION PUMP CONTROL CIRCUIT OPEN
GROUND CIRCUIT OPEN
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Press the Residual Engine Heat Utilization (REST) switch off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Circulation Pump harness connector.
Connect a 12-volt test light between the Circulation Pump Control circuit and the
Ground circuit in the Circulation Pump harness connector. The test light should
operate as follows:
With the Residual Engine Heat Utilization (REST) switch off, the test light should
not illuminate.
Press the Residual Engine Heat Utilization (REST) switch on. The test light should
illuminate brightly.
Does the test light function as specified?All
Yes, Light Only Illuminates With REST On
Replace the Circulation Pump in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
No, Light Illuminates With REST Off
Go To 2
No, Light Will Not Illuminate
Go To 3
2 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Circulation Pump harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Turn the ignition on.
Measure the voltage of the Circulation Pump Control circuit.
Is the voltage above 0.2 volts?All
Ye s!Repair the Circulation Pump Control circuit for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
152
HEATING & A/C

Symptom:
RECIRC AIR SOLENOID CONTROL HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
RECIRCULATED AIR SOLENOID VALVE
RECIRCULATED AIR SOLENOID VALVE CONTROL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
RECIRCULATED AIR SOLENOID VALVE CONTROL CIRCUIT OPEN
GROUND CIRCUIT OPEN
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition on.
Press the Air Recirculation switch off.
Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Recirculated Air Solenoid Valve harness connector.
Connect a 12-volt test light between the Recirculated Air Solenoid Valve Control
circuit and the Ground circuit in the Recirculated Air Solenoid harness connector.
Turn the ignition on. The test light should operate as follows:
With the Air Recirculation switch off, the test light should not illuminate.
Press the Air Recirculation switch on. The test light should illuminate brightly.
Does the test light function as specified?All
Yes, Light Only Illuminates w/Recirc On
Replace the Recirculated Air Solenoid Valve in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No, Light Illuminates w/Recirc Off
Go To 2
No, Light Will Not Illuminate
Go To 3
2 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Recirculated Air Solenoid Valve harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Turn the ignition on.
Measure the voltage of the Recirculated Air Solenoid Valve Control circuit.
Is the voltage above 0.2 volts?All
Ye s!Repair the Recirculated Air Solenoid Valve Control circuit for a
short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
167
HEATING & A/C

TEST ACTION APPLICABILITY
4 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Reconnect the Automatic Temperature Control (ATC) C1 harness connector.
Disconnect the Recirculated Air Solenoid Valve harness connector.
Turn the ignition on.
Press the Air Recirculation switch off.
Turn the ignition off.
Connect a 12-volt test light between the Recirculated Air Solenoid Valve Control
circuit and the Ground circuit in the Recirculated Air Solenoid harness connector.
Turn the ignition on. The test light should operate as follows:
With the Air Recirculation switch off, the test light should not illuminate.
Press the Air Recirculation switch on. The test light should illuminate brightly.
Does the test light function as specified?All
Ye s!Replace the Recirculated Air Solenoid Valve in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
170
HEATING & A/C
RECIRC AIR SOLENOID CONTROL SHORTED LOW (ACTIVE) ÐContinued

Symptom:
WATER CYCLE VALVE CONTROL HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
WATER CYCLE VALVE
WATER CYCLE VALVE CONTROL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
WATER CYCLE VALVE CONTROL CIRCUIT OPEN
GROUND CIRCUIT OPEN
AUTOMATIC TEMPERATURE CONTROL (ATC)
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Press the Residual Engine Heat Utilization (REST) switch off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Water Cycle Valve harness connector.
Connect a 12-volt test light between the Water Cycle Valve Control circuit and the
Ground circuit in the Water Cycle Valve harness connector. The test light should
operate as follows:
With the Residual Engine Heat Utilization (REST) switch off, the test light should
not illuminate.
Press the Residual Engine Heat Utilization (REST) switch on.
With the Blend control set to Full Cold, the test light should illuminate brightly and
continuously.
With the Blend control set to one position below the half Cold/Hot setting, the test
light should illuminate brightly and blink at a slow continuous rate.
With the Blend control set to the half Cold/Hot setting or above, the test light should
be off.
Does the test light operate as specified?All
Ye s!Replace the Water Cycle Valve in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
No, Light Illuminates With REST Off.
Go To 2
No, Light Will Not Illuminate
Go To 3
No, Light Won't Correspond To Blend
Go To 3
175
HEATING & A/C