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Home >> Suzuki >> 2001 >> Grand Vitara JLS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1408: Manifold Absolute Pressure (Map) Sensor Circuit Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P1408 is set, go to next step. If DTC P1408 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Connect scan tool. Turn ignition on. Using scan tool, check MAP. If reading is 78.7 kPA or more or 63.5 kPa or less, go to next step. If reading is not 78.7 kPA or more or 63.5 kPa or less, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  3. Turn ignition off. Disconnect MAP sensor connector. Check for poor terminal contact at MAP sensor connector. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, turn ignition on. Measure voltage between ground and MAP sensor harness connector terminals No. 1 (Red/White wire) and No. 3 (Gray/Red wire), individually. If 4-6 volts exist, go to step  6. If 4-6 volts do not exist, go to next step.
    4. NOTE: If a short to battery voltage occurred in Red/White wire between MAP sensor and PCM 26-pin connector C51-3 terminal No. 13, MAP sensor may have also been damaged.
  4. Check for open or short in Red/White wire between MAP sensor and PCM 26-pin connector C51-3 terminal No. 13. Also check for open or short to ground in Gray/Red wire between MAP sensor and PCM 26-pin connector C51-3 terminal No. 11. If wires are okay, go to next step.
  5. Disconnect PCM 26-pin connector C51-3. Check for poor terminal contact at PCM 26-pin connector C51-3. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, check MAP sensor operation. See SYSTEM & COMPONENT TESTING article. Repair or replace as necessary. If MAP sensor is okay, replace PCM and go to DTC CONFIRMATION TEST .
  6. Check MAP sensor operation. See SYSTEM & COMPONENT TESTING article. Repair or replace as necessary. If MAP sensor is okay, go to next step.
  7. Check for short between Red/White wire and Gray/Red wire. If wires are okay, check for open in Gray/Yellow wire between MAP sensor and PCM 26-pin connector C51-3 terminal No. 20. If wire is okay, disconnect PCM 26-pin connector C51-3. Check for poor terminal contact at PCM 26-pin connector C51-3. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, replace PCM and go to DTC CONFIRMATION TEST .
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