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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1996 🢒 Chevy G Van 🢒 Engine 🢒 Engine Controls - 6.5L 🢒 DTC P1635 5 Volt Reference Circuit

Object Number: 52968 Size: MF
Engine Controls Components
Engine Data Sensors
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The PCM provides a 5 volt supply for use in powering up the sensors. This test monitors the voltage present at terminals BRD13 (shared by Boost and Crankshaft Position sensors) and BRD14 (the Optical/Fuel temperature sensor (Cam/HI. Res)). This is a type D DTC.

Conditions for Setting the DTC

5 volt reference is less than 1 volt.

Action Taken When the DTC Sets
    • Backup fuel
    • No turbo boost

Conditions for Clearing the MIL/DTC
    • A History DTC will clear after forty consecutive warm-up cycles during which the diagnostic does not fail (the coolant temperature has risen 5°C (40°F) from the start up coolant temperature and the engine coolant temperature exceeds 71°C (160°F) during that same ignition cycle).
    • Use of a Scan tool will clear the DTC codes.

Diagnostic Aids

During the time the failure is present, the setting of additional DTCs that share a 5 volt reference may also set.

Test Description

The number(s) below refer to the Step number(s) on the Diagnostic Table.

  1. Checks to confirm that a DTC is still present.

    2.

  2. Checks to determine if there is a 5 volt reference from the PCM.

    3.

  3. Checks to determine if there is a short-to-ground in the reference circuit or a short-to-ground in the PCM.

Step

Action

Value(s)

Yes

No

1

Important: Before clearing the DTCs, use the Scan Tool Capture Info in order to record the Freeze Frame and the failure records for reference, as the data will be lost when the Clear Info function is used.

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. The Scan Tool is installed.
  2. Crank the engine for 15 seconds or start up.

Does the DTC reset?

--

Go to Step 3

Go to Step 5

3

  1. Turn the ignition ON with the engine OFF.
  2. Disconnect the Boost sensor.
  3. Use a J 39200 DVM in order to probe 5 volt reference circuit at the harness connector.

Is the voltage less than the specified value?

4.0V

Go to Step 4

Go to Step 6

4
  1. Disconnect the PCM connector with the Boost sensor 5 volt reference circuit.
  2. With a test light connected to B+, probe the 5 volt reference circuit at the PCM harness.

Is the test light ON?

--

Go to Step 7

Go to Step 8

5

The DTC is intermittent. If no additional DTCs are stored, refer to the Diagnostic Aids. If any additional DTCs were stored, refer to those table(s).

Are there any additional DTCs stored?

--

Go to the applicable DTC table

Go to Diagnostic Aids

6

Replace the Boost sensor. Refer to Boost Sensor (Diesel) .

Is the action complete?

--

Go to Step 8

--

7

Repair a short to ground in a 5 volt reference circuit.

Is the action complete?

--

Go to Step 8

--

8

Replace the PCM.

Important: If the PCM is malfunctioning, the new PCM must be programmed.

Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 9

--

9
  1. Use the Scan Tool in order to select DTC, Clear Info.
  2. Start the engine.
  3. Allow the engine to idle at the normal operating temperature.
  4. Select DTC, Specific, then enter the DTC number which was set.
  5. 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 10

Go to Step 2

10

Use the Scan Tool in order to select Capture Info, Review Info.

Are there any DTCs displayed that have not been diagnosed?

--

Go to the Applicable DTC table

System OK