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 P1651 sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1651 Service Vehicle Soon (SVS) Lamp Control Circuit Low 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 P1651 runs continuously once the above conditions are met. |
Conditions for Setting the DTC
The ECM detects an open or a short to ground 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 numbers below refer to the step numbers on the diagnostic table.
-
This step tests the control circuit for a shorted to ground.
-
This step tests the control circuit for an open.
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 P0650 set? | -- | Go to Step 3 | Go to Step 4 | ||||||
3 | Are DTCs P0654 and P0656 set? | -- | Go to Step 15 | Go to Step 5 | ||||||
4 |
Did the DTC fail this ignition? | -- | Go to Step 5 | Go to Intermittent Conditions | ||||||
Does the service vehicle soon (SVS) illuminate? | -- | Go to Step 14 | Go to Step 6 | |||||||
6 |
Does the SVS illuminate? | -- | Go to Step 13 | Go to Step 7 | ||||||
7 |
Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 15 | ||||||
Does the test lamp illuminate? | -- | Go to Step 9 | Go to Step 14 | |||||||
9 |
Is the resistance less than the specified value? | 3 ohms | Go to Step 10 | Go to Step 14 | ||||||
10 | Measure the resistance of the control circuit of the SVS from the ECM harness connector terminal to the IPC harness connector terminal. Is the resistance less than the specified value? | 3 ohms | Go to Step 11 | Go to Step 14 | ||||||
11 |
Is the resistance within the specified range? | 10-18 ohms | Go to Step 12 | Go to Step 16 | ||||||
12 | Test for shorted terminals and poor connections at the IPC. 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 19 | Go to Step 17 | ||||||
13 | 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 19 | Go to Step 18 | ||||||
14 | Repair the control circuit of the SVS for one of the following conditions:
Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 19 | -- | ||||||
15 | Repair the ignition 1 voltage circuit of the SVS for one of the following conditions:
Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 19 | -- | ||||||
16 | Replace the SVS lamp. Refer to Instrument Cluster Bulb Replacement in Instrument Panel, Gages, and Console. Did you complete the replacement? | -- | Go to Step 19 | -- | ||||||
17 | Replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console. Did you complete the replacement? | -- | Go to Step 19 | -- | ||||||
18 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 19 | -- | ||||||
19 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 20 | ||||||
20 | Are there any DTCs that have not been diagnosed? | -- | System OK | |||||||
