A control module measured supply voltage below its calibrated threshold for the required time.
Why this matters
A trouble code reports a monitored result. It narrows the system and test conditions, but it rarely names the failed part by itself.
Evidence to capture first
- Code-setting module and freeze-frame voltage
- Battery state of charge and capacity
- Charging command, generator output, belt condition, and loaded voltage drop on positive and ground paths
A disciplined path
- Stabilize and test the battery
- Reproduce electrical load while comparing voltage at the battery and affected module
- Measure voltage drop across cables and connections
- Confirm charging control and output using service information
Decision point
The repair is supported when the failed circuit, mechanical condition, or monitored response is measured and the original monitor can run without the fault returning.
Source desk
Use current model-specific service information for specifications, connector locations, disabling procedures, and tightening values. The following public resources support the broader safety or system context used in this guide.
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