Pinpoint Test AI: DTC B1318

Instrumentation and Warning Chimes

Pinpoint Tests

Pinpoint Test AI: DTC B1318

Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information. Diagrams By Number

Normal Operation
- DTC B1318 (Battery Voltage Low) - sets in continuous memory and on-demand if the Instrument Cluster (IC) voltage drops below 9 volts on the B+ keep alive voltage input circuit.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- High circuit resistance
- IC

PINPOINT TEST AI: DTC B1318

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.

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AI1 RECHECK THE IC DTCs

- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC Self-Test.
- Clear the DTCs. Repeat the IC self-test.
- Is DTC B1318 still present?

Yes
GO to AI2.

No
The system is operating correctly at this time. The DTC may have been set due to a previous low battery voltage condition.

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AI2 CHECK THE CHARGING SYSTEM DTCs IN THE PCM

- Enter the following diagnostic mode on the scan tool: PCM Self-Test.
- Retrieve the continuous memory DTCs from all modules.
- Is DTC P0620, P0622, P0625, P0626 or P065B set in the PCM?

Yes
REFER to Charging System Testing and Inspection.

No
GO to AI3.

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AI3 CHECK THE BATTERY CONDITION AND STATE OF CHARGE

- Check the battery condition and verify that the battery is fully charged. Refer to Battery, Mounting and Cables Testing and Inspection.
- Is the battery OK and fully charged?

Yes
GO to AI4.

No
REFER to Battery, Mounting and Cables Testing and Inspection.

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AI4 CHECK THE IC VOLTAGE PID

- Ignition ON.
- Measure and record the voltage at the battery.
- Enter the following diagnostic mode on the scan tool: IC DataLogger.
- Monitor the IC voltage PID (VBAT_1).
- Is the voltage within 0.2 volt of the recorded battery voltage?

Yes
GO to AF7.

No
GO to AF5.
AI5 CHECK THE IC VOLTAGE SUPPLY

- Ignition OFF.
- Disconnect: IC C220a.
- Ignition ON.
- Measure the voltage between the IC C220a-10, circuit SBP33 (RD), harness side and ground.




- Is the voltage within 0.2 volt of the recorded battery voltage?

Yes
GO to AF6.

No
REPAIR the circuit for high resistance. CLEAR the DTC. REPEAT the self-test.
AI6 CHECK THE IC GROUND CIRCUITS

- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the IC, harness side and ground as follows:









- Is the resistance less than 5 ohms?

Yes
GO to AF7.

No
REPAIR the circuit for high resistance. CLEAR the DTCs. REPEAT the self-test.
AI7 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. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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