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Home >> Suzuki >> 2006 >> Forenza Premium, 4D Wagon, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control Systems >> Engine Performance - DTC P1391 - P2610, DTC U0073 >> DTC P1391: Rough Road Sensor Performance >> Troubleshooting
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DTC P1391: Rough Road Sensor Performance: Troubleshooting

TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an On-Board Diagnostic (OBD II) System Check.
Is the system check complete?		 - Go to Step 2 Go to On-Board Diagnostic (OBD II) System Check
2
  1. Turn the ignition ON, with engine OFF.
  2. Install a scan tool to the Data Link Connector (DLC).
  3. Review and record the scan tool Failure Records data.
  4. Operate the vehicle within Failure Records conditions as noted.
  5. Using the scan tool, monitor specific Diagnostic Trouble Code (DTC) info for DTC P1391.

Does the scan tool indicate that DTC P1391 failed?		 - Go to Step 4 Go to Step 3
3 Check for the following conditions and repair as needed:
  • G sensor seal missing or damaged.
  • G sensor mounting flanges cracked, missing or incorrectly installed.

Is the repair complete?		 - Go to Step 14 Go to Diagnostic Aids
4
  1. Turn the ignition OFF.
  2. Disconnect the G sensor electrical connector.
  3. Turn the ignition ON, with the engine OFF.
  4. Observe the G sensor value displayed on the scan tool.

Is the G sensor value near the specified value?		 0 V Go to Step 5 Go to Step 12
5
  1. Jumper the 5 volt reference circuit, terminal A and the G sensor signal circuit, terminal B together at the G sensor harness connector.
  2. Observe the G sensor value displayed on the scan tool.

Is the G sensor value near the specified value?		 4.95 V Go to Step 6 Go to Step 7
6
  1. Turn the ignition OFF.
  2. Disconnect the Engine Control Module (ECM) and check the sensor ground circuit for high resistance, an open between the ECM and the G sensor or for a poor connection at the terminal C4 of the ECM and repair as needed.
  3. If the problem is found, repair as necessary.

Is a problem found?		 - Go to Step 14 Go to Step 10
7 Check the 5 volt reference circuit for high resistance, an open between the ECM and the G sensor or a poor connection at the terminal C2 of the ECM and repair as needed.
Is the repair complete?		 - Go to Step 14 Go to Step 8
8
  1. Turn the ignition OFF.
  2. Disconnect the ECM and check the G sensor signal circuit for high resistance, an open, a short to ground or a short to the sensor ground circuit and repair as needed.

Is the repair complete?		 - Go to Step 14 Go to Step 9
9 Check the G sensor signal circuit for a poor connection at the ECM and repair as needed.
Is the repair complete?		 - Go to Step 14 Go to Step 13
10 Check for a poor connection at terminal C of the G sensor and repair as needed.
Is the repair complete?		 - Go to Step 14 Go to Step 11
11 Replace the G sensor.
Is the repair complete?		 - Go to Step 14 -
12
  1. Turn the ignition OFF.
  2. Disconnect the ECM.
  3. Turn the ignition ON.
  4. Check the G sensor signal circuit for a short to voltage or a short to the 5 volt reference circuit and repair as needed.

Is the repair complete?		 - Go to Step 14 Go to Step 13
13
  1. Turn the ignition OFF.
  2. Replace the ECM.

Is the repair complete?		 - Go to Step 14 -
14
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic ran and passed?		 - Go to Step 15 Go to Step 2
15 Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?		 - Go to applicable DTC table System OK
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