Code result
P0AC4
Hybrid/EV Powertrain Control Module Requested MIL Illumination
High severity
What it means
The hybrid powertrain control module has requested MIL illumination via the inter-module bus. Underlying fault is reported separately by the requesting module.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Downstream fault in hybrid system
highOne of the most commonly reported causes for this code — check this first.
Communication lag - MIL request stale
mediumA plausible cause — test and verify before replacing parts.
Related help
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