Pinpoint Test Q: The Transfer Case Control Module (TCCM) Does Not Respond To The Scan Tool
Communications Network
Pinpoint Tests
Pinpoint Test Q: The Transfer Case Control Module (TCCM) Does Not Respond To The Scan Tool
Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information. Diagrams By Number
Refer to Wiring Diagram Set 34, Four Wheel Drive Systems for schematic and connector information. Diagrams By Number
Normal Operation
The Transfer Case Control Module (TCCM) communicates with the scan tool through the High Speed Controller Area Network (HS-CAN).
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- TCCM
PINPOINT TEST Q: THE TCCM DOES NOT RESPOND TO THE SCAN TOOL
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery, Mounting and Cables Battery Disconnect / Connect.
-------------------------------------------------
Q1 CHECK THE TCCM CONTROL MODULE VOLTAGE SUPPLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: TCCM C2371a and C2371b .
- Ignition ON.
- Measure the voltage between the TCCM C2371b-7, circuit CBB53 (GY/BN), harness side and ground.
- Measure the voltage between the TCCM C2371a-6, circuit SBB84 (GN/RD), harness side and ground; and between the TCCM C2371a-7, circuit SBB40 (VT/RD), harness side and ground.
- Are the voltages greater than 10 volts?
Yes
GO to Q2.
No
VERIFY the Battery Junction Box (BJB) fuses 40 (15A), 53 (20A) and 84 (30A) are OK. If OK, REPAIR the circuit in question. If not OK, Refer to Wiring Diagrams to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool. Diagrams By Number
-------------------------------------------------
Q2 CHECK THE TCCM GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable .
- Measure the resistance between the TCCM C2371a-3, circuit GD124 (BK/VT), harness side and ground; and between the TCCM C2371a-10, circuit GD124 (BK/VT), harness side and ground.
- Are the resistances less than 5 ohms?
Yes
GO to Q3.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
-------------------------------------------------
Q3 CHECK THE HS-CAN CIRCUITS BETWEEN THE TCCM AND THE DLC FOR AN OPEN
- Measure the resistance between the TCCM C2371b-10, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side.
- Measure the resistance between the TCCM C2371b-9, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
- Are the resistance less than 5 ohms?
Yes
CONNECT the negative battery cable. GO to Q4.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
-------------------------------------------------
Q4 CHECK FOR CORRECT TCCM OPERATION
- Disconnect all the TCCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the TCCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new TCCM. REFER to Four Wheel Drive (4WD) Systems . CLEAR the DTCs. REPEAT the network test with the scan tool.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
-------------------------------------------------