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.
This diagnostic procedure supports the following DTC:
DTC P0562 System Voltage Low
• | The ignition is ON. |
• | DTC P0562 runs continuously once the above conditions are met. |
• | 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. |
• | 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. |
• | 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. |
• | 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 |
The number below refers to the step number on the diagnostic table.
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: Component Connector End Views | ||||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||||
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 |
Is the voltage difference less than the specified value? | 1 V | Go to Step 4 | Go to Step 5 | ||||||||
4 |
Did the DTC fail this ignition? | -- | Go to Step 5 | Go to Testing for Intermittent Conditions and Poor Connections | ||||||||
Do you hear an audible click when the relay is commanded ON? | -- | Go to Step 8 | Go to Step 6 | |||||||||
6 |
Is the resistance less than the specified value? | 3 Ω | Go to Step 7 | Go to Step 16 | ||||||||
7 |
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. Is the voltage less than the specified value? | 2.5 V | Go to Step 14 | Go to Step 13 | ||||||||
8 |
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. Is the voltage less than the specified value? | 0.1 V | Go to Step 10 | Go to Step 17 | ||||||||
10 |
Is the voltage difference less than the specified value? | 1 V | Go to Step 14 | Go to Step 11 | ||||||||
11 |
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:
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 |
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? | -- | System OK |