What causes P1129 on a Honda?

MAP sensor stuck high from internal failure Open vacuum supply hose venting the sensor to atmosphere Short to voltage in the MAP signal wire ECM/PCM reference voltage fault

How do I fix P1129 on a Honda?

Compare MAP, BARO, and TP readings on an HDS scan tool at idle and key-off Check the MAP vacuum hose routing and manifold port for blockage or leaks Test signal and reference circuits for shorts or opens Replace the MAP sensor only after wiring and vacuum prove good Clear codes and verify MAP drops normally on deceleration

P1129 MAP Sensor Signal Higher Than Expected

Q: What does P1129 mean on a Honda?

P1129 — MAP Sensor Signal Higher Than Expected. Applies to Civic, Accord, CR-V, Odyssey, Pilot.

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Civic, Accord, CR-V, Odyssey, Pilot

What does P1129 mean on a Honda?

P1129 — MAP Sensor Signal Higher Than Expected. This Honda-enhanced code applies to Civic, Accord, CR-V, Odyssey, Pilot.

Common causes of P1129

MAP sensor stuck high from internal failure
Open vacuum supply hose venting the sensor to atmosphere
Short to voltage in the MAP signal wire
ECM/PCM reference voltage fault

How to fix P1129

Compare MAP, BARO, and TP readings on an HDS scan tool at idle and key-off
Check the MAP vacuum hose routing and manifold port for blockage or leaks
Test signal and reference circuits for shorts or opens
Replace the MAP sensor only after wiring and vacuum prove good
Clear codes and verify MAP drops normally on deceleration