DIAGNOSIS Required Special Tools • MB991958: Scan tool (MUT-III Sub Assembly) MB991824: V.C.I. MB991827: USB Cable MB991911: Main Harness B

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Turn the ignition switch to the "ON" position. (3) Set scan tool MB991958, read the DTC. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the diagnostic trouble code other than P0069 set? YES: Refer to, Diagnostic Trouble Code Chart . NO: Go to Step 2.

STEP 2. Using scan tool MB991958, check data list item 95: Manifold Absolute Pressure Sensor. (1) Turn the ignition switch to the "ON" position. (2) Set scan tool MB991958 to the data reading mode for item 95, Manifold Absolute Pressure Sensor. • When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg). • When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg). • When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 in.Hg). • When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 in.Hg). (3) Start the engine. • When the engine is idling, 16 - 36 kPa (4.7 - 10.6 in.Hg). • When the engine is suddenly revved, manifold absolute pressure varies. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the sensor operating properly? YES: Go to Step 3. NO: Refer to, DTC P0106 - Manifold Absolute Pressure Circuit Range/Performance Problem , DTC P0107 - Manifold Absolute Pressure Circuit Low Input , DTC P0108 - Manifold Absolute Pressure Circuit High Input .

STEP 3. Using scan tool MB991502 or MB991958, check data list item 25: Barometric Pressure Sensor. (1) Start the engine and run at idle. (2) Set scan tool MB991958 to the data reading mode for item 25, Barometric Pressure Sensor. When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg). When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg). When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 in.Hg). When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 in.Hg). (3) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the sensor operating properly? YES: Go to Step 4. NO: Refer to, DTC P2228 - Barometric Pressure Circuit Low Input , DTC P2229 - Barometric Pressure Circuit High Input .

STEP 4. Using scan tool MB991958, read the diagnostic trouble code (DTC). (1) Turn the ignition switch to the "ON" position. (2) Erase the DTC. (3) Start the engine. (4) Turn the ignition switch to "LOCK" (OFF) position and then wait 2 seconds. (5) Turn the ignition switch to the "ON" position. (6) Set scan tool MB991958, read the DTC. (7) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is DTC P0069 set? YES: Replace the ECM or PCM. Then go to Step 5. NO: It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions .