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Home >> Isuzu >> 2007 >> i-290 LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System & Fuel System - 2.9L - DTC P0134 To DTC P0420 >> DTC P0327 >> Test Description

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  This step ensures that the malfunction is present.
  2. 3:  This step tests for a KS that is shorted to ground
  3. 4:  This step tests the KS for proper operation.
  4. 5:  This step tests for a short to voltage on the KS signal circuit.
DTC P0327

Step Action Values Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2 
IMPORTANT: If an engine mechanical noise can be heard, repair the condition before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical .
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Does the DTC fail this ignition?		 - Go to Step 3  Go to Diagnostic Aids
3 
  1. Turn OFF the ignition.
  2. Disconnect the knock sensor (KS).
  3. Set the DMM to the ohm scale.
  4. Measure the resistance from the KS signal terminal A to a good ground with the DMM.
  5. Measure the resistance from the KS signal terminal B to a good ground with the DMM.
Does the DMM display OL for both terminals?		 - Go to Step 4  Go to Step 10 
4 
  1. Connect the DMM between the terminals of the affected KS.
  2. Set the DMM to the 400 mV AC hertz scale and wait for the DMM to stabilize at 0 Hz. Refer to Measuring Frequency .
    3. IMPORTANT: DO NOT tap on plastic engine components.
  3. Tap on the engine block with a non-metallic object near the affected KS while observing the signal indicated on the DMM.
Does the DMM display a fluctuating frequency while tapping on the engine block?		 - Go to Step 5  Go to Step 10 
5 
  1. Turn ON the ignition, with the engine OFF.
  2. Measure the voltage at the KS signal circuit terminal A to a good ground with a DMM.
  3. Measure the voltage at the KS signal circuit terminal B to a good ground with a DMM.
Does the DMM display a voltage above the specified value on either circuit?		 4.2 V Go to Step 6  Go to Step 7 
6
  1. Turn OFF the ignition
  2. Disconnect the powertrain control module (PCM).
  3. Test the KS signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 12  Go to Step 11 
7
  1. Turn OFF the ignition.
  2. Disconnect the PCM.
  3. Test the KS signal circuit for an open, for a high resistance, and for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 12  Go to Step 9 
8 Test for an intermittent and for a poor connection at the affected KS. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 - Go to Step 12  Go to Step 10 
9 Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 - Go to Step 12  Go to Step 11 
10 Replace the affected KS. Refer to Knock Sensor Replacement .
Did you complete the replacement?		 - Go to Step 12  -
11 Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?		 - Go to Step 12  -
12
  1. Clear the DTCs with a scan tool.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Does the DTC fail this ignition?		 - Go to Step 2  Go to Step 13 
13 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle System OK
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