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Test Db: Manifold Absolute Pressure/Barometer Sensor: Testing

    NOTE: For additional testing information, see DIAGNOSTIC AIDS .

  1. 1) DTC P0105: Check MAP/BARO Sensor MAP/BP_V PID Reading
    DTC P0105 indicates PCM received an excessively high or low voltage, a high voltage under light load driving conditions, or a low voltage under heavy driving conditions from MAP/BARO sensor. Possible causes are as follows:
    • MAP/BARO sensor circuit is open, or shorted to GND or VPWR.
    • Hoses between intake manifold and MAP/BARO sensor are disconnected or clogged.
    • Inoperative MAP/BARO switch solenoid valve.
    • Faulty MAP/BARO sensor.

    Disconnect vacuum line to MAP/BARO sensor and solenoid. Check for restrictions and leaks. Repair as necessary. Connect scan tool to DLC. Turn ignition on. Using scan tool, access MAP/BP_V PID from PID/DATA MONITOR & RECORD menu. If MAP/BP_V PID reading is more than 2.6 volts, leave ignition on, scan tool connected and go to next step. If MAP/BP_V PID reading is 2.6 volts or less, go to step  4).

  2. 2) Check MAP/BARO Sensor

    Disconnect vacuum line to MAP/BARO sensor. Connect vacuum pump to MAP/BARO sensor inlet. Apply 2.99 in. Hg of vacuum to MAP/BARO sensor. Using scan tool, access MAP/BP_V PID from PID/DATA MONITOR & RECORD menu. If MAP/BP_V PID reading is 2.6 volts or more, go to next step. If MAP/BP_V PID reading is less than 2.6 volts, system is operating properly at this time. Go to INTERMITTENTS in TROUBLE SHOOTING - NO CODES - VILLAGER article to check for intermittent concern.

  3. 3) Check MAP/BARO Circuit For Open

    Turn ignition off. Disconnect MAP/BARO sensor harness connector. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Using DVOM, measure resistance of MAP/BARO circuit between MAP/BARO sensor connector and PCM harness connector terminal No. 41 (Pink wire). See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in circuit. See WIRING DIAGRAMS article.

  4. 4) Check MAP/BARO Sensor Circuit For Short To Ground

    Turn ignition off. Disconnect PCM and MAP/BARO sensor harness connectors, if not already done. Using DVOM, measure resistance between MAP/BARO and GND circuits at PCM harness connector terminals. See PCM TERMINAL CIRCUIT IDENTIFICATION  and MAP/BARO & MAP/BARO SOL CIRCUIT IDENTIFICATION  tables. See Figure and Figure . If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between affected circuits or to ground. See WIRING DIAGRAMS article.

  5. 5) Check MAP/BARO Circuit For Short To Power

    Ensure ignition is off. Using DVOM, measure resistance between MAP/BARO and VPWR circuits at PCM harness connector. See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between affected circuits or to power. See WIRING DIAGRAMS article.

  6. 6) Check VREF Circuit

    Reconnect PCM harness connector. Turn ignition on. Using DVOM, measure voltage between negative battery terminal and VREF circuit at MAP/BARO sensor harness connector. See Figure. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, repair open or short to ground in VREF circuit. See WIRING DIAGRAMS article.

  7. 7) Check SIG RTN Circuit For Open

    Turn ignition off. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Using DVOM, measure resistance of SIG RTN circuit between MAP/BARO sensor harness connector terminal No. 1 (Blue wire) and PCM harness connector terminal No. 58 (Black/Yellow wire). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in SIG RTN circuit between PCM and MAP/BARO sensor.

  8. 8) Check SIG RTN Circuit For Short To Ground

    Ensure ignition is off. Using DVOM, measure resistance between SIG RTN and GND circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION  table. See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between affected circuits. See WIRING DIAGRAMS article.

  9. 9) Check SIG RTN Circuit For Short To Power

    Ensure ignition is off. Using DVOM, measure resistance between SIG RTN and VPWR circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION  table. See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between affected circuits.

  10. 10) Check MAP/BARO Sensor Function

    Connect scan tool to DLC. Ensure engine is at normal operating temperature. Ensure MAP/BARO sensor and PCM connectors are connected. Disconnect MAP/BARO sensor vacuum line. Turn ignition on, with engine off. Using scan tool, access MAP/BP_V PID from PID/DATA MONITOR & RECORD menu. If MAP/BP_V PID reading is 3.2-4.8 volts, replace PCM. If MAP/BP_V PID reading is not 3.2-4.8 volts, replace MAP/BARO sensor.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 10)  to step 15)  . No test procedures have been omitted.
    11. NOTE: For additional testing information, see DIAGNOSTIC AIDS .

  11. 15) DTC P1105: Check MAP/BARO Vacuum Line
    DTC P1105 indicates there is little difference between KOEO and KOER voltage signals of MAP/BARO sensor received by PCM. Possible causes are as follows:
    • MAP/BARO switch solenoid circuit is open, or shorted to PWR or GND.
    • Faulty MAP/BARO switch solenoid.
    • Hoses kinked or improper connection to intake manifold, or air intake to MAP/BARO pressure sensor.
    • Faulty MAP/BARO pressure sensor.

    Turn ignition off. Disconnect vacuum lines from MAP/BARO sensor and solenoid. Inspect vacuum lines for restrictions or leaks. Repair or replace as necessary. If vacuum lines are okay, go to next step.

  12. 16) Check MAP/BARO Solenoid IGN START/RUN Circuit

    Disconnect MAP/BARO solenoid harness connector. Turn ignition on. Using DVOM, measure voltage between negative battery terminal and IGN START/RUN circuit at MAP/BARO solenoid harness connector terminal No. 2 (Blue/Yellow wire). See Figure. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open in Blue/Yellow wire. See WIRING DIAGRAMS article.

  13. 17) Check MAP/BARO SOL Circuit For Short To Ground

    Turn ignition off. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Using DVOM, measure resistance between negative battery terminal and MAP/BARO SOL circuit at MAP/BARO solenoid harness connector terminal No. 1 (Violet wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Violet wire.

  14. 18) Check MAP/BARO SOL Circuit For Open

    Ensure ignition is off. Using DVOM, measure resistance of MAP/BARO SOL circuit (Violet wire) between MAP/BARO solenoid harness connector terminal No. 1 and PCM harness connector terminal No. 98. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Violet wire. See WIRING DIAGRAMS article.

  15. 19) Check MAP/BARO Solenoid Operation

    Remove MAP/BARO solenoid. Connect a jumper wire between battery power and solenoid terminal No. 2. Connect another jumper wire between negative battery terminal and solenoid terminal No. 1. Blow air into port "A" of MAP/BARO solenoid. There should be air flow between ports "A" and "C", and no air flow between ports "B" and "C". Remove both jumper wires from solenoid. Blow air into port "A". There should be air flow between ports "B" and "C", and no air flow between ports "A" and "C". See Figure. Replace solenoid if operation is not as specified. If solenoid operates as specified, replace PCM.
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