Slow cranking and module undervoltage codes were caused by resistance at a body ground, not by the recently installed battery.
Why this matters
The value of this case is the order of evidence and the verification step. The same symptom on another vehicle may have a different cause.
Evidence to capture first
- Battery capacity
- Cranking voltage
- Positive and ground voltage drop
- Ground-eyelet condition
A disciplined path
- Test battery state first
- Measure both cable paths during cranking
- Disassemble the supported suspect joint
- Clean or replace the approved connection and protect it
Decision point
Cranking speed and module voltage recovered after the ground path met the loaded-drop specification.
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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