2006 MERCEDES-BENZ SPRINTER ignition

Symptom:
SYSTEM UNDERVOLTAGE
When Monitored and Set Condition:
SYSTEM UNDERVOLTAGE
When Monitored: Always monitored with system active at each ignition cycle.
Set Condition: Ignition voltage falls below 8.5 volts with the engine rpm greater than
2000 rpm for 60 seconds.
POSSIBLE CAUSES
ENGINE CHARGING SYSTEM DTC'S PRESENT
TRANSMISSION RELAY OUTPUT LO AT TCM
TCM - SYSTEM UNDER VOLTAGE
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the service information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 With the DRBIIIt, read Engine DTC's.
Are there any Engine Charging System DTC's present?All
Ye s!Refer to the Charging category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
109
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
3 Turn the ignition off to the lock position.
Disconnect the TCM C1 harness connector.
Start the engine.
Increase the Engine Speed to 1500 RPM.
Measure the voltage of the Transmission Relay Output circuit in the TCM C1
harness connector.
Is the voltage below 9.0 volts?All
Ye s!Repair the Transmission Relay Output circuit for an open or high
resistance.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
11 0
TRANSMISSION - NAG1
SYSTEM UNDERVOLTAGE ÐContinued

Symptom:
TCC SOLENOID CIRCUIT
When Monitored and Set Condition:
TCC SOLENOID CIRCUIT
When Monitored: Always monitored with system active at each ignition cycle.
Set Condition: If the TCM detects a short to ground or battery on the solenoid control
circuit, shorted solenoid, open solenoid, or an open or shorted solenoid control circuit driver
in the TCM.
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
TCC SOLENOID CONTROL CIRCUIT OPEN
TCC SOLENOID CONTROL CIRCUIT SHORT TO GROUND
TCC SOLENOID CONTROL CIRCUIT SHORT TO OTHER CIRCUITS
TCC SOLENOID
TCM - TCC SOLENOID CIRCUIT
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the service information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
11 2
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
2 Ignition on, engine not running.
With the DRBIIIt, erase DTCs.
With the DRBIIIt, perform the Solenoid Test.
With the DRBIIIt, read DTCs.
Did the DTC, TCC SOLENOID CIRCUIT, reset?All
Ye s!Go To 3
No!Go To 7
3 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the TCC Solenoid Control circuit from the TCM C2 harness
connector to the Transmission Solenoid Assembly harness connector.
Is the resistance above 5.0 ohms?All
Ye s!Repair the TCC Solenoid Control circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the TCC Solenoid Control circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the TCC Solenoid Control circuit for a short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 5
5 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the TCC Solenoid Control circuit to all other circuits in the
Transmission Solenoid Assembly harness connector.
Is the resistance below 5.0 ohms between any other circuit?All
Ye s!Repair the TCC Solenoid Control circuit for a short to other
circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 6
6 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between the TCC Solenoid Control circuit and the Solenoid
Supply Voltage circuit in the Transmission Control Module C2 harness connector.
Is the resistance between 2.0 and 4.0 ohms?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the TCC Solenoid per the Service Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
11 3
TRANSMISSION - NAG1
TCC SOLENOID CIRCUIT ÐContinued

TEST ACTION APPLICABILITY
2 Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid Assembly harness connector.
Start the engine.
With the brakes firmly applied, shift the gear selector into Drive.
Did the engine stall or stumble?All
Ye s!Repair the internal transmission. Pay particular attention to the
components related to the TCC. Refer to the Service Information
for the proper repair procedure.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance between ground and the TCC Solenoid Control circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the TCC Solenoid Control circuit for a short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid harness connector.
Measure the resistance of the TCC Solenoid Control circuit to all other circuits in the
Transmission Solenoid harness connector.
Is the resistance below 5.0 ohms on any circuit?All
Ye s!Repair the TCC Solenoid Control circuit for a short to other
circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
11 6
TRANSMISSION - NAG1
TCC STUCK ON ÐContinued

Symptom:
TRANS TEMP SENSOR - P/N SWITCH CIRCUIT
When Monitored and Set Condition:
TRANS TEMP SENSOR - P/N SWITCH CIRCUIT
When Monitored: Always monitored with system active at each ignition cycle.
Set Condition: Temp sensor is open while in forward gears (1-5), temp sensor, open Trans
temp circuit, P/N Switch.
POSSIBLE CAUSES
SHIFTER ADJUSTMENT
SENSOR GROUND CIRCUIT OPEN
TEMP SENSOR - P/N SWITCH CIRCUIT OPEN
TEMP SENSOR - P/N SWITCH CIRCUIT SHORT TO GROUND
SENSOR GROUND CIRCUIT SHORT TO OTHER CIRCUITS
TEMP SENSOR- P/N SWITCH CIRCUIT SHORT TO OTHER CIRCUITS
TEMP SENSOR - P/N SWITCH
TCM - TEMP SENSOR - P/N SWITCH
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the service information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
11 7
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
2 Check the Shifter Assembly adjustment per the Service Information.
Was the Shifter Assembly adjusted correctly?All
Ye s!Go To 3
No!Adjust the Shifter Assembly per the Service Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
3 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance of the Sensor Ground circuit between the TCM C2 harness
connector and the Transmission Solenoid Assembly harness connector.
Is the resistance above 5.0 ohms?All
Ye s!Repair the Sensor Ground circuit for an open or high resistance.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance of the Transmission Temp Sensor - P/N Switch circuit
between the TCM C2 harness connector and the Transmission Solenoid Assembly
harness connector.
Is the resistance above 5.0 ohms.All
Ye s!Repair the Transmission Temp Sensor - P/N Switch circuit for an
open.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 5
5 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance between ground and the Transmission Temp Sensor - P/N
Switch circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the Transmission Temp Sensor - P/N Switch circuit for a
short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 6
6 Turn the ignition off to the lock position.
Disconnect the TCM C1 and C2 harness connectors.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance between the Sensor Ground circuit and all other circuits in
the TCM C1 and C2 harness connectors.
Is the resistance below 5.0 ohms on any of the circuits?All
Ye s!Repair the Sensor Ground circuit for a short to other circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 7
11 8
TRANSMISSION - NAG1
TRANS TEMP SENSOR - P/N SWITCH CIRCUIT ÐContinued

TEST ACTION APPLICABILITY
7 Turn the ignition off to the lock position.
Disconnect the TCM C1 and C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance between the Temp Sensor - P/N Switch circuit and all other
circuits in the TCM C1 and C2 harness connector.
Is the resistance below 5.0 ohms on any circuit?All
Ye s!Repair the Transmission Temp Sensor - P/N Switch circuit for a
short to other circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 8
8 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
NOTE: Make sure the Transmission Solenoid Assembly harness connector is
connected or the results of the test will be invalid.
With the brakes firmly applied, place the gear selector in Drive.
Measure the resistance between the Temp Sensor - P/N Switch circuit and the Sensor
Ground circuit in the TCM C2 harness connector.
Is the resistance between 500 and 2500 ohms?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Temp Sensor - P/N Switch Assembly per the Service
Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
11 9
TRANSMISSION - NAG1
TRANS TEMP SENSOR - P/N SWITCH CIRCUIT ÐContinued