What does code P1602 mean?

Q: What does code P1602 mean?

PCM to ABS Module Communication Problem. P1602 on a GM vehicle means the powertrain control module (PCM) has lost or detected a fault in its serial data communication link with the anti-lock brake system (ABS) module. The PCM sets this code when it cannot reliably exchange messages with the ABS controller over the vehicle's data bus, so it flags the communication circuit rather than a brake hydraulic fault.

DTC codes / GM codes / P1602

P1602 · GMPCM to ABS Module Communication Problem

P1602 on a GM vehicle means the powertrain control module (PCM) has lost or detected a fault in its serial data communication link with the anti-lock brake system (ABS) module. The PCM sets this code when it cannot reliably exchange messages with the ABS controller over the vehicle's data bus, so it flags the communication circuit rather than a brake hydraulic fault.

SystemPowertrain

Code typeGM specific

SeverityMedium

Fix difficultyProfessional

AreaComputer and output circuits

Guidance is general and written for GM vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.