P1659 Electronic Throttle System Control Relay Off Malfunction

Category: Powertrain - Computer and Auxiliary Controls
Severity: Check Engine Light
Applies to: Civic, Accord, CR-V with drive-by-wire

What does P1659 mean on a Honda?

P1659 — Electronic Throttle System Control Relay Off Malfunction. This Honda-enhanced code applies to Civic, Accord, CR-V with drive-by-wire.

Common causes of P1659

Failed ETCS control relay stuck off
Open relay control circuit
Blown ETCS fuse
Corroded relay socket
ECM relay driver fault

How to fix P1659

Swap the ETCS relay with a known-good unit
Check ETCS fuses
Test relay command voltage
Inspect the socket
Verify throttle operation returns