DTC P0562. Chevrolet Joy 2008

For 1990-2009 cars

### Circuit Description

The engine control module (ECM) monitors the voltage supplied on the feedback circuit of the engine controls ignition relay or the main relay. Voltage that is out of range will cause incorrect input readings from the engine components connected to the relay. If the ECM detects low voltage on the feedback circuit of the main relay, this DTC sets.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0562 System Voltage Low

### Conditions for Running the DTC

• | The ignition is ON.

• | DTC P0562 runs continuously once the above conditions are met.

### Conditions for Setting the DTC

• | The ECM detects the voltage on the feedback circuit of the main relay is less than 5 volts for 7.6 seconds.

• | The ECM detects the ignition voltage is less than 11.5 volts.

### Action Taken When the DTC Sets

• | The malfunction indicator lamp (MIL) will not illuminate.

• | The ECM will store conditions which were present when the DTC was set as Failure Records data only.

• | This information will not be stored in the Freeze Frame data.

### Conditions for Clearing the MIL/DTC

• | A history DTC will clear after 40 consecutive warm-up cycles without a fault.

• | DTCs can be cleared by using the scan tool.

• | Disconnect the ECM battery feed for more than 10 seconds.

### Diagnostic Aids

• | For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections .

• | The following table illustrates the MAIN relay terminal location in the underhood fuse block.

Main Relay Terminal Identification
Control
B+ - Coil | Feedback
B+ - Switch
Front of Vehicle

### Test Description

The number below refers to the step number on the diagnostic table.

1. Listen for an audible click when the relay operates. Repeat the commands as necessary.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic References: Engine Controls Schematics for the 0.8 L engine or Engine Controls Schematics for the 1.0 L engine Connector End View References: Engine Controls Connector End Views for the 0.8 L engine or Engine Controls Connector End Views for the 1.0 L engine
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Are DTCs P1610 or P1611 also set? | -- | Diagnose P1610 or P1611 first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle | Go to Step 3

3

1. Start the engine.
2. Measure the voltage at the battery with a DMM.
3. Observe the Ignition 1 Signal parameter with a scan tool.
4. Subtract the battery voltage from the voltage indicated on the Ignition 1 Signal parameter.

Is the voltage difference less than the specified value?

1 V

Go to Step 4

Go to Step 5

4

1. Observe the Freeze Frame/Failure Records data for this DTC.
2. Turn OFF the ignition for 30 seconds.
3. 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.

Did the DTC fail this ignition?

--

Go to Step 5

Go to Testing for Intermittent Conditions and Poor Connections

5

1. Turn ON the ignition, with the engine OFF.
2. With a scan tool, command the engine controls ignition relay or the main relay ON.

Do you hear an audible click when the relay is commanded ON?

--

Go to Step 8

Go to Step 6

6

1. Turn OFF the ignition.
2. Disconnect the main relay.
3. Disconnect the appropriate engine control module (ECM) fuse in the underhood fuse block.
4. Measure the resistance of the battery positive circuit of the main relay coil from the appropriate ECM fuse terminal to the relay terminal.

Is the resistance less than the specified value?

3 ohms

Go to Step 7

Go to Step 16

7

1. Turn ON the ignition, with the engine OFF.

Important: Use the J 35616-200 Test Lamp Kit for this test. If the J 35616-200 is not available, use a test lamp that measures between 25-30 ohms.

2. Probe the control circuit of the main relay with a test lamp connected to battery positive voltage.
3. Measure the voltage from the probe of the test lamp to a good ground with a DMM.

Is the voltage less than the specified value?

2.5 V

Go to Step 14

Go to Step 13

8

1. Turn OFF the ignition.
2. Disconnect the main relay.
3. Probe the battery positive circuit of the main relay switch with a test lamp connected to a good ground.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 17

9

Important: Use the J 35616-200 for this test. If the J 35616-200 is not available, use a test lamp that measures between 25-30 ohms.

1. Probe the battery positive circuit of the main relay switch with a test lamp connected to a good ground.
2. Measure the voltage from the probe of the test lamp to battery positive voltage with a DMM.

Is the voltage less than the specified value?

0.1 V

Go to Step 10

Go to Step 17

10

1. Connect a 15-amp fused jumper wire from battery positive voltage to the main relay switched output terminal at the fuseblock for the feedback circuit of the main relay.
2. Turn ON the ignition, with the engine OFF.
3. Measure the voltage at the battery with a DMM.
4. Observe the Ignition 1 Signal parameter with a scan tool.
5. Subtract the battery voltage from the voltage indicated on the Ignition 1 Signal parameter.

Is the voltage difference less than the specified value?

1 V

Go to Step 14

Go to Step 11

11

1. Turn OFF the ignition.
2. Disconnect the ECM.
3. Connect a 15-amp fused jumper wire from battery positive voltage to the main relay switched output terminal at the fuseblock for the feedback circuit of the main relay.
4. Connect a test lamp from the feedback circuit of the main relay at the harness connector of the ECM to a good ground.

Does the test lamp illuminate?

--

Go to Step 12

Go to Step 18

12 | Important: Use the J 35616-200 for this test. If the J 35616-200 is not available, use a test lamp that measures between 25-30 ohms. Measure the voltage from the probe of the test lamp to battery positive voltage with a DMM. Is the voltage less than the specified value? | 0.3 V | Go to Step 15 | Go to Step 18
13 | Test the control circuit of the main relay for high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 21 | Go to Step 15
14 | Test for an intermittent or poor connection at main relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 21 | Go to Step 19
15 | Test for an intermittent or poor connection at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 21 | Go to Step 20
16 | Repair the high resistance in the battery positive voltage circuit of the main relay coil. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 21 | --
17 | Repair the high resistance in the battery positive voltage circuit of the main relay switch. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 21 | --

18

Repair the feedback circuit of the main relay for one of the following conditions:

• | An open

• | High resistance

| Important: If a short to ground is indicated by an open ENG MAIN fuse, test all circuits protected by the fuse.

• | A short to ground

Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 21

--

19 | Replace the main relay. Did you complete the replacement? | -- | Go to Step 21 | --
20 | Replace the ECM. Did you complete the replacement? | -- | Go to Step 21 | --

21

1. Clear the 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 the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 22

22 | 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