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Manifold Absolute Pressure (MAP) Sensor

NOTE: Terminal identification letters are stamped on MAP sensor body.
  1. Disconnect electrical connector from sensor. With ignition on and engine stopped, measure voltage output of sensor terminal "B". See Fig 1 . Ensure wiring harness is okay by also measuring voltage at ECU terminal "C-t". Output voltage should be 4-6 volts at both points. Repair or replace wiring harness as required.
  2. With ignition on and engine stopped, measure supply voltage of sensor terminal "C". See Fig 1 . Ensure wiring harness is okay by also measuring voltage at ECU terminal "C-14". Supply voltage should be 4.4-5.5 volts at both points. Repair or replace wiring harness as required.
  3. Using an ohmmeter, measure ground circuit resistance at sensor terminal "A" and ECU connector terminal "D-3". Ensure wiring harness is okay by also measuring resistance between ECU terminal "D-3" and "B-11". If ohmmeter indicates an open circuit, check for defective sensor ground connection at right side of cylinder block.
  4. If ground connection is okay, replace ECU. If ECU terminal "D-3" has short to 12-volts, repair wire before replacing ECU. Repair or replace wiring harness as required.
Fig 1: MAP Sensor Terminal Identification
G12418