Pinpoint Test C: The Instrument Cluster (IC) Does Not Respond To The Scan Tool
Communications Network
Pinpoint Tests
Pinpoint Test C: The Instrument Cluster (IC) 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 60, Instrument Cluster for schematic and connector information. Diagrams By Number
Normal Operation
The Instrument Cluster (IC) communicates with the scan tool through the High Speed Controller Area Network (HS-CAN) and the Medium Speed Controller Area Network (MS-CAN). Circuits VDB04 (WH/BU) (HS-CAN +) and VDB05 (WH) (HS-CAN -) provide the HS-CAN connection to the IC and circuits VDB06 (GY/OG) (MS-CAN +) and VDB07 (VT/OG) (MS-CAN -) provide the MS-CAN connection to the IC. Voltage for the IC is provided by circuits CBP29 (WH/VT) and 1566 (RD/YE). Circuit GD111 (BK/BU) provides ground.
The IC shares the HS-CAN with the following modules:
- PCM
- Steering Effort Control Module (SECM)
- ABS module
- Restraints Control Module (RCM)
- 4X4 control module
- Accessory Protocol Interface Module (APIM)
The IC shares the MS-CAN with the following modules:
- Audio Control Module (ACM)
- Rear Entertainment Module (RETM)
- Driver Seat Module (DSM)
- HVAC module
- Accessory Protocol Interface Module (APIM)
- Liftgate/Trunk Module (LTM)
- Satellite Digital Audio Receiver System (SDARS) module
- Smart Junction Box (SJB)
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- IC
PINPOINT TEST C: THE IC 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.
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C1 CHECK THE HS-CAN TERMINATION RESISTANCE
- Ignition OFF.
- NOTE: Failure to disconnect the battery will result in false resistance readings.
- Disconnect the battery ground cable.
- Disconnect the scan tool cable from the Data Link Connector (DLC).
- Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
- Is the resistance between 54 and 66 ohms?
Yes
GO to C2.
No
GO to C4.
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C2 CHECK THE IC VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Disconnect: IC C220.
- Connect the battery ground cable.
- Ignition ON.
- Measure the voltage between the IC, harness side and ground as follows:
- Are the voltages greater than 10 volts?
Yes
GO to C3.
No
VERIFY the SJB fuses 26 (10A) or 29 (5A) are OK. If OK, REPAIR the circuit in question. If not OK, Refer to the Wiring Diagrams to identify the possible causes of the short circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
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C3 CHECK THE IC GROUND CIRCUITS
- Ignition OFF.
- Measure the resistance between the IC, harness side and ground as follows:
- Are the resistances less than 5 ohms?
Yes
GO to C4.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
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C4 CHECK THE HS-CAN CIRCUITS BETWEEN THE IC AND THE DATA LINK CONNECTOR (DLC) FOR AN OPEN
- Measure the resistance between the IC C220-7, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side.
- Measure the resistance between the IC C220-8, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to C5.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
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C5 CHECK THE MS-CAN CIRCUITS BETWEEN THE IC AND THE DLC FOR AN OPEN
- Measure the resistance between the IC C220-4, circuit VDB06 (GY/OG), harness side and the DLC C251-3, circuit VDB06 (GY/OG), harness side.
- Measure the resistance between the IC C220-5, circuit VDB07 (VT/OG), harness side and the DLC C251-11, circuit VDB07 (VT/OG), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to C6.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
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C6 CHECK FOR CORRECT IC OPERATION
- Disconnect the IC connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IC connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new IC. 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. CLEAR the DTCs. REPEAT the network test with the scan tool.
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