What causes a P188C code?

P188C can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P188C code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P188C active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

OBD-II

P188C

Air pressure sensor out of range high

What it means

The ECM has detected that the ambient air pressure sensor signal voltage is higher than the maximum calibrated limit (typically above 4.8V).