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DTC P0108: Map Sensor Volts Too High

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.
NOTE: MAP sensor voltage is monitored when engine speed is more than 600 RPM but less than 3500 RPM and Throttle Position (TP) sensor voltage is less than one volt. DTC may be stored in Powertrain Control Module (PCM) when PCM senses MAP sensor voltage is more than 4.9 volts at start or with engine running for 2 seconds. Possible causes are: defective Manifold Absolute Pressure (MAP) sensor, defective PCM, or defective connectors or wiring.
  1. Start engine and allow to idle. Using scan tool, read MAP sensor voltage. If MAP sensor voltage is more than 4.6 volts, go to next step. If MAP sensor voltage is 4.6 volts or less, go to step  7.
  2. Turn ignition off. Note location of Manifold Absolute Pressure (MAP) sensor on the intake manifold. See Figure. MAP sensor contains a 3-pin connector. Disconnect connector at MAP sensor. Connect jumper wire between MAP sensor connector terminals No. 1 (Black/Light Blue wire) and No. 3 (Dark Green/Red wire). Turn ignition on. Using scan tool, read MAP sensor voltage. If MAP sensor voltage is one volt or more, go to next step. If MAP sensor voltage is less than one volt, replace MAP sensor. Perform TEST VER-5A .
  3. Turn ignition off. Remove jumper wire. Turn ignition on with engine off. MAP sensor voltage will update with cycle of the ignition. Using voltmeter, check voltage at terminal No. 3 (Dark Green/Red wire) on connector for MAP sensor. If voltage is 5.5 volts or less, go to next step. If voltage is more than 5.5 volts, repair short to voltage on Dark Green/Red wire between PCM and MAP sensor. Perform TEST VER-5A  PCM is located in engine compartment, between air cleaner and radiator.
  4. Turn ignition off. Using ohmmeter, check resistance between MAP sensor connector terminals No. 2 (Violet/White wire) and No. 3 (Dark Green/Red wire). If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short between MAP sensor signal (Dark Green/Red wire) and 5-volt supply (Violet/White wire) circuits between PCM and MAP sensor. Perform TEST VER-5A .
  5. Disconnect PCM connectors. PCM is located in engine compartment, between air cleaner and radiator. Using ohmmeter, check resistance of Dark Green/Red wire between MAP sensor connector terminal No. 3 and PCM connector terminal No. 36. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open circuit on Dark Green/Red wire between PCM and MAP sensor. Perform TEST VER-5A .
  6. Ensure ignition is off. Using ohmmeter, check resistance of Black/Light Blue wire between MAP sensor connector terminal No. 1 and PCM connector terminal No. 43. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-5A . If resistance is 5 ohms or more, repair open circuit on Black/Light Blue wire between PCM and MAP sensor. Perform TEST VER-5A .
  7. Start engine and allow engine to idle. Wiggle wiring harness and connectors from MAP sensor to PCM while monitoring MAP sensor voltage. If MAP sensor voltage does not change while wiggling wiring harness and connectors, go to next step. If MAP sensor voltage changes while wiggling wiring harness and connectors, repair wiring or connectors between MAP sensor and PCM as necessary that caused the voltage to change. Perform TEST VER-5A .
  8. Inspect wiring and connectors between MAP sensor and PCM. If no problems exist, test is complete. If any problems exist, repair wiring or connectors as necessary. Perform TEST VER-5A .
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