DTC P1235: Manifold Absolute Pressure (MAP) Sensor Supply Voltage High/Low
- Check the ''On Board Diagnostic (OBD) System Check''.
Was the ''OBD System Check'' performed?
YES – Go to step 2.
NO – Go to OBD System Check. 
- Check the DTC.
Are there other DTCs P1628, P1627 (beside DTC P1235) being output?
YES – Go to step 3.
NO – Clear DTC P1235 by the scan tool.
- Turn the ignition switch ON (II).
- Check the MAP with the scan tool.
Is about atmospheric pressure indicated?
YES – Go to step 5.
NO – Go to step 7.
- Start the engine and allow it to idle.
- Check the MAP with the scan tool.
Is about 20 – 30 kPa (150 – 225 mmHg, 5.9 – 8.9 in. Hg) indicated?
YES – Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the MAP sensor and at the ECM.
NO – Go to step 7.
- Turn the ignition switch OFF.
- Disconnect the MAP sensor 3P connector.
- Check the MAP with the scan tool.
Is about 250 kPa (1,877 mmHg, 73 in. Hg) indicated?
YES – Go to step 10.
NO – Substitute a known-good ECM and recheck. If symptom/indication goes away, replace the original ECM.
- Check the MAP sensor signal and supply circuit for B+ short.
Is a problem found?
YES – Repair open in the signal wire or supply wire between ECM and the MAP sensor.
NO – Substitute a known-good ECM and recheck. If symptom/indication goes away, replace the original ECM.
| NOTICE |
The battery power supply short circuit to 5 V power supply damages the ECM.