2006 MERCEDES-BENZ SPRINTER engine

TEST ACTION APPLICABILITY
2 Ignition on, engine not running.
With the DRBIIIt, read Transmission DTCs.
NOTE: If the DTC, CAN BUS CIRCUIT is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
3 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any Engine Temperature Sensor DTCs present?All
Ye s!Refer to the Driveability category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Replace and program the ECM per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Start the engine.
With the brakes firmly applied, shift the gear selector into drive.
With the DRBIIIt, read Transmission DTCs.
Did the DTC, ENGINE TEMP MESSAGE, reset?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test complete.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
65
TRANSMISSION - NAG1
ENGINE TEMP MESSAGE ÐContinued

Symptom:
ENGINE TORQUE MESSAGE INCORRECT
When Monitored and Set Condition:
ENGINE TORQUE MESSAGE INCORRECT
When Monitored: Valid Torque CAN messages received at least once and CAN Bus
Circuit, Engine CAN Message Missing and Engine CAN Message Incorrect are not active.
Set Condition: Engine torque message not valid or PCM/ECM controller error.
POSSIBLE CAUSES
ENGINE DTCS PRESENT
PCM/ECM - ENGINE TORQUE MESSAGE INCORRECT
TCM - TORQUE MESSAGE INCORRECT
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 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any performance or bus related Engine DTCs present?All
Ye s!Refer to the Powertrain category and perform the appropriate
symptom.
No!Go To 3
66
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
3 Replace and program the ECM per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Drive the vehicle performing multiple aggressive upshifts and downshifts.
With the DRBIIIt, read Transmission DTCs.
Did the DTC, ENGINE TORQUE MESSAGE INCORRECT, reset?All
Ye s!Go To 4
No!Test Complete
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
4 If there are no possible causes remaining, view repair. All
Repair
Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
67
TRANSMISSION - NAG1
ENGINE TORQUE MESSAGE INCORRECT ÐContinued

Symptom:
ENGINE TORQUE REDUCTION
When Monitored and Set Condition:
ENGINE TORQUE REDUCTION
When Monitored: Engine intervention active for at least 20 ms, no engine torque errors,
engine torque demand is greater than 0.
Set Condition: Torque Reduction acknowledge bit - not set, no shift aborts, the error flag
9torque reduction acknowledge9is not set, Engine controller not supporting torque
requests.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
CAN C BUS +/- CIRCUIT OPEN
ENGINE DTCS PRESENT
PCM/ECM - ENGINE CAN MESSAGE MISSING
TCM - ENGINE CAN MESSAGE MISSING
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
68
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
2 Ignition on, engine not running.
With the DRBIIIt, read Transmission DTCs.
NOTE: If the DTC CAN BUS CIRCUIT is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off to the lock position.
Disconnect the PCM/ECM harness connector(s).
Disconnect the TCM C2 harness connector.
Measure the resistance of the CAN C Bus + circuit between the PCM/ECM harness
connector and the TCM C2 harness connector.
Measure the resistance of the CAN C Bus - circuit between the PCM/ECM harness
connector and the TCM C2 harness connector.
Is the CAN C Bus + or - circuit open?All
Ye s!Repair the CAN C BUS + or - circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any performance or bus related Engine DTCs present?All
Ye s!Refer to the Powertrain category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 5
5 Replace and program the PCM/ECM per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Start the engine.
With the brakes firmly applied, shift the gear selector into drive.
With the DRBIIIt, read Transmission DTCs.
Did the DTC, ENGINE CAN MESSAGE MISSING, reset?All
Ye s!Go To 6
No!Test Complete
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
6 If there are no possible causes remaining, view repair. All
Repair
Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
69
TRANSMISSION - NAG1
ENGINE TORQUE REDUCTION ÐContinued

Symptom:
IC CAN MESSAGE INCORRECT
When Monitored and Set Condition:
IC CAN MESSAGE INCORRECT
When Monitored:
Set Condition: CAN Bus messages received from the Instrument Cluster are incorrect.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
INSTRUMENT CLUSTER DTCS PRESENT
OPEN CAN CIRCUITS AT INSTRUMENT CLUSTER
INSTRUMENT CLUSTER
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 Ignition on, engine not running.
With the DRBIIIt, read Transmission DTCs.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
No!Go To 3
70
TRANSMISSION - NAG1

TEST ACTION APPLICABILITY
3 Ignition on, engine not running.
With the DRBIIIt, read Instrument Cluster DTCs.
Are there any Instrument Cluster DTCs present?All
Ye s!Refer to the INSTRUMENT CLUSTER category and perform the
appropriate symptom.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the Instrument Cluster C1 harness connector.
Measure the resistance between the CAN C Bus (+) circuit and the CAN C Bus (-)
circuit in the Instrument Cluster harness connector.
Is the resistance 60 ohms,   3.0 ohms?All
Ye s!Replace the Instrument Cluster per the service information.
No!Repair the CAN C Bus (+) or the CAN C Bus (-) circuit for an open.
71
TRANSMISSION - NAG1
IC CAN MESSAGE INCORRECT ÐContinued

Symptom:
IC/ATC CAN MESSAGE MISSING
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
AUTOMATIC TEMP CONTROL DTCS PRESENT
INSTRUMENT CLUSTER DTCS PRESENT
OPEN CAN BUS CIRCUITS AT INSTRUMENT CLUSTER
OPEN CAN BUS CIRCUITS AUTOMATIC TEMP CONTROL
AUTOMATIC TEMP CONTROL
INSTRUMENT CLUSTER
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 Ignition on, engine not running.
With the DRBIIIt, read Transmission DTCs.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
No!Go To 3
3NOTE: NOTE: If vehicle is equipped with Air Conditioning diagnose the ATC
system first.
Is the vehicle equipped with air conditioning?All
Ye s!Go To 4
No!Go To 6
72
TRANSMISSION - NAG1