Circuit Description
The VIM controls the operation of the SECURITY indicator lamp by providing ground at terminal M. Lamp control is based upon inputs from the following components:
| • | The VCM (Class 2 Data, terminal C and terminal D) |
| • | The ignition switch (Ignition 1, terminal J, CKT 39) |
| • | The brake pedal (Stop Lamps, terminal L) |
| • | The SECURITY indicator (SECURITY Indicator Control, terminal M) |
| • | The signals received from the transmitter in the key fob |
Conditions for Setting the DTC
When the VIM is commanding the lamp to turn off, and the voltage is measured at the VIM terminal M is less than 2 volts, DTC B0687 is set.
Conditions for Clearing the MIL/DTC
- A history DTC will clear after 100 consecutive ignition cycles occur without a fault.
- Use the Scan Tool in order to clear the history and the current DTCs.
Diagnostic Aids
Most intermittent faults are caused by a faulty electrical connection or the wiring. Damaged VIM's are occasionally at fault. Refer to Intermittent and Poor Connections in Troubleshooting Procedures for a detailed explanation of how to locate and repair intermittent conditions.
Test Description
The number(s) below refer to the step number(s) in the Security System Indicator Circuit Low Table.
-
This test identifies the malfunction as lamp does not come on (open circuit) or lamp always on (short to ground).
-
This test inspects for an open power feed fuse to the lamp
-
This test inspects for a circuit malfunction causing the open fuse.
-
This test inspects that the Vehicle Immobilizer Module (VIM) is receiving the ignition 1 signal (no open in the power feed wire).
-
This test inspects for an open indicator lamp bulb.
-
This test inspects for an open in the SECURITY indicator control circuit.
-
This test inspects for bad connections that prevent the lamp from lighting.
-
This test inspects for a short to ground in the SECURITY indicator control circuit.
-
This test determines if the malfunction is due to a short to ground in the SECURITY indicator control circuit.
Step | Action | Value(s) | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 |
| ||||||||
2 | Turn the ignition switch to the RUN position. Did the SECURITY lamp light? | -- | Go to Step 16 | Go to Step 3 | ||||||||
3 |
Is the GAUGES fuse (Fuse 4) open? | -- | Go to Step 4 | Go to Step 7 | ||||||||
4 | Inspect for a short to ground in CKT 39. Was a short to ground in CKT 39 found? | -- | Go to Step 5 | Go to Step 6 | ||||||||
5 |
Is the repair complete? | -- |
| -- | ||||||||
6 |
Is the repair complete? | -- |
| -- | ||||||||
7 |
Do the Dome And Courtesy lamps come on and then go off when the ignition switch is turned to the RUN position? | -- | Go to Step 9 | Go to Step 8 | ||||||||
8 |
Is the repair complete? | -- |
| -- | ||||||||
9 |
Is the SECURITY indicator bulb open? | -- | Go to Step 10 | Go to Step 11 | ||||||||
10 |
Is the repair complete? | -- |
| -- | ||||||||
11 |
Is the resistance within the specified range? | Less than 5ohms | Go to Step 13 | Go to Step 12 | ||||||||
12 |
Is the repair complete? | -- |
| -- | ||||||||
13 |
Are all of the connections good? | -- | Go to Step 14 | Go to Step 15 | ||||||||
14 |
Is the repair complete? | -- |
| -- | ||||||||
15 |
Is the repair complete? | -- |
| -- | ||||||||
16 |
Is the resistance at or above the specified value? | OL (infinite) | Go to Step 18 | Go to Step 17 | ||||||||
17 |
Is the repair complete? | -- |
| -- | ||||||||
18 |
Does the SECURITY lamp light? | -- | Go to Step 19 | Go to Step 20 | ||||||||
19 |
Is the repair complete? | -- |
| -- | ||||||||
20 |
Is the repair complete? | -- |
| -- |
