Circuit Description
The service vehicle soon (SVS) lamp is located on the instrument panel cluster. The SVS lamp will illuminate when there is a non-emission related failure or the ignition is ON with the engine OFF. Ignition 1 voltage is supplied to the SVS lamp. The engine control module (ECM) turns the SVS lamp ON by grounding the control circuit of the SVS lamp using a low side driver. The ECM monitors the voltage level on the control circuit of the SVS lamp. If the ECM detects a short to voltage on the control circuit of the SVS lamp, DTC P1650 sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1650 Service Vehicle Soon (SVS) Lamp Control Circuit High Voltage
Conditions for Running the DTC
| • | The ignition is ON or the engine is operating. |
| • | The ignition 1 voltage is more than 10 volts. |
| • | DTC P1650 runs continuously once the above conditions are met. |
Conditions for Setting the DTC
The ECM detects a short to voltage on the control circuit of the SVS lamp.
Action Taken When the DTC Set
| • | The malfunction indicator lamp (MIL) will illuminate after 3 consecutive trips with a fail. |
| • | The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffers. |
Conditions for Clearing the MIL/DTC
| • | The MIL will turn OFF after 4 consecutive ignition cycles in which the diagnostic runs without a fault. |
| • | DTCs can be cleared by using the scan tool. |
| • | Disconnect the ECM battery feed for more than 10 seconds. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |
2 |
Does DTC P1650 set? | -- | Go to Step 4 | Go to Step 3 |
3 |
Did the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions |
Does the SVS lamp illuminate? | -- | Go to Step 5 | Go to Step 6 | |
5 | Test for shorted terminals and poor connections at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 7 |
6 | Repair a short to voltage on the control circuit of the SVS lamp. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 8 | -- |
7 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 8 | -- |
8 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 9 |
9 | Are there any DTCs that have not been diagnosed? | -- | System OK | |
