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For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptors

    • DTC P0697 5-volt Reference 3 Circuit Open
    • DTC P0698 5-volt Reference 3 Circuit low voltage
    • DTC P0699 5-volt Reference 3 Circuit high

Circuit Description

The control module has 3 internal 5-volt reference busses called 5-volt  reference 1, 5-volt reference 2 and 5-volt reference 3. Each reference bus provides 5-volt reference circuits for more than one sensor. Therefore, a fault condition on one 5-volt reference circuit will affect other 5-volt reference circuits connected to that reference bus. The control module monitors the voltage on the 5-volt reference busses.

The 5-volt reference 3 bus provides 5 volts to the following sensors:

    • The TP Sensors 1 and 2
    • The Accelerator Pedal Position (APP) sensor 1

Conditions for Running the DTC

    • Turn the ignition switch ON
    • The engine control module (ECM) power relay is turned ON
    • P0697, P0698 or P0699 continuously run once the above condition is present for 3 seconds.

Conditions for Setting the DTC

The control module detects for an open, a short to ground or a short to the voltage on the 5-volt reference 3 circuit.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, last test failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

Diagnostic Aids

    • Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.
    • The lower connector of the ECM is connector C1 and the upper connector of the ECM is connector C2. Refer to Engine Controls Component Views .
    • For an intermittent condition, refer to Intermittent Conditions .

Step

Action

Value

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Engine Control Module Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Observe the Freeze Frame/Failure Records for this DTC .
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate he 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. Disconnect the throttle position (TP) sensor 1 and 2 electrical connector.
  2. Turn the ignition switch ON, with the engine OFF. Measure the Voltage parameter between throttle position (TP) sensor terminal 2 on the 5-volt reference circuit and the ground.

Is the voltage within the specified value?

4.8-5.2 V

Go to Step 10

Go to Step 4

4

Is the voltage more than the specified value?

5.2 V

Go to Step 5

Go to Step 6

5

Test the 5-volt reference circuit of the APP sensors 1 and the throttle position (TP) sensors 1 and 2 for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 8

6

Is the voltage less than the specified value?

4.8 V

Go to Step 7

--

7

Test the 5-volt reference circuit of the APP sensors 1 and the throttle position (TP) sensors 1 and 2 for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 8

8

  1. Measure continuously the Voltage parameter between throttle position (TP) sensor 1 and 2 terminal 2 on the 5-volt reference circuit and the ground.
  2. Observe the DMM while disconnecting APP sensor 1.

Is the voltage return to the specified value?

4.8-5.2 V

Go to Step 9

Go to Step 13

9

Replace the accelerator pedal position (APP) sensor . Refer to Accelerator Pedal Position Sensor Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

  1. Connect the throttle position (TP) sensor 1 and 2 connector, disconnect the accelerator pedal position (APP) sensor 1 electrical connector.
  2. Measure the Voltage parameter between the APP sensor 1 terminal C on the 5-volt reference circuit and the ground with a DMM.

Is the voltage within the specified range?

4.8-5.2 V

Go to Step 14

Go to Step 11

11

Test the TP sensor 1 and 2 signal circuit for a short to voltage, or a mulfunction of the TP sensor 1 and 2. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 12

12

Replace the throttle position (TP) sensor 1 and 2. Refer to Throttle Body Assembly Replacement .

Did you complete the replacement?

--

Go to Step 14

--

13

Replace the ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 14

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14

  1. Clear any DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate he 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 15

15

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