Seat Belt Indicator Malfunction - Driver
Diagnostic Instructions
Diagnostic Fault Information
Circuit
|
Short to Ground
|
High Resistance
|
Open
|
Short to Voltage
|
Signal Performance
|
Driver Seat Belt Switch Signal
|
1
|
2
|
2
|
2
|
-
|
Driver Seat Belt Switch Low Reference
|
-
|
2
|
2
|
2
|
-
|
1. Indicator will remain ON with seat belt buckled.
2. Indicator will illuminate only for the bulb check.
|
|
|
Circuit/System Description
The driver seat belt switch is a 2-wire switch wired to the
inflatable restraint sensing and diagnostic module (SDM) using a
signal circuit and a low reference circuit. When the seat belt is
unbuckled the switch is closed, and when the seat belt is buckled
the switch is open. The SDM sends the status of the driver seat
belt via serial data to the instrument panel cluster. After
receiving the message, the instrument panel cluster controls the
illumination of the driver seat belt indicator.
Reference Information
Schematic Reference
Seat Belt Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Seat Belt System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
1. |
Command the instrument cluster
all indicators ON and OFF with a scan tool. The driver seat belt
indicator should turn ON and OFF as commanded. |
⇒ If the driver seat
belt indicator does not turn ON and OFF as commanded
⇒ |
Replace the P16 instrument cluster. |
⇓ If the driver seat
belt indicator does turn ON and OFF as commanded
2. |
Monitor the scan tool Driver
Seat Belt Switch parameter while buckling and unbuckling the seat
belt. The parameter should display Buckled and Unbuckled when
changing seat belt states. |
⇒ If the scan tool
Driver Seat Belt Switch parameter does not display Buckled and
Unbuckled when changing seat belt states
⇒ |
Refer to Circuit/System Testing. |
⇓ If the scan tool
Driver Seat Belt Switch parameter does display Buckled and
Unbuckled when changing seat belt states
Circuit/System Testing
Note: When removing
connectors inspect for damage or corrosion. Damage or corrosion in
the following requires repair or replacement of the affected
component/connector.
• |
Seat belt switch
harness connector |
• |
SDM wiring harness
connector |
2. |
Disconnect the harness
connector at the B88 seat belt switch. |
3. |
Test for less than 5 Ω
between the low reference circuit terminal 2 and ground.
|
⇒ If 5 Ω or
greater
|
3.1 |
Disconnect the harness
connector at the K36 SDM. |
|
3.2 |
Test for less than 2 Ω
in each control circuit end to end. |
⇒ |
If 2 Ω or greater, repair the open/high resistance in the
circuit. |
⇒ |
If less than 2 Ω, replace the K36 SDM. |
5. |
Verify the scan tool Driver
Seat Belt Status parameter displays Buckled. |
⇒ If the scan tool
Driver Seat Belt Status parameter does not display
Buckled
|
5.1 |
Disconnect the harness
connector at the K36 SDM. |
|
5.2 |
Test for infinite resistance
between the seat belt switch signal circuit terminal 1 and
ground. |
⇒ |
If less than infinite resistance, repair the short to ground on
the circuit. |
⇒ |
If less than 2 Ω, replace the K36 SDM. |
⇓ If the scan tool
Driver Seat Belt Status parameter does display
Buckled
6. |
Install a 3 A fused jumper
wire between the signal circuit terminal 1 and the low reference
circuit terminal 2. |
7. |
Verify the scan tool Driver
Seat Belt Status parameter displays Unbuckled. |
⇒ If the scan tool
Driver Seat Belt Status parameter does not display
Unbuckled
|
7.1 |
Disconnect the harness
connector at the K36 SDM. |
|
7.3 |
Test for less than 1 V between
the signal circuit and ground. |
⇒ |
If 1 V or greater, repair the short to voltage on the
circuit. |
|
7.4 |
Test for less than 2 Ω
in each circuit end to end. |
⇒ |
If 2 Ω or greater, repair the open/high resistance in the
circuit. |
⇒ |
If less than 2 Ω, replace the K36 SDM. |
⇓ If the scan tool
Driver Seat Belt Status parameter does display
Unbuckled
8. |
Replace the B88 seat belt
switch. |
Component Testing
2. |
Disconnect the harness
connector at the B88 seat belt switch. |
3. |
B88 seat belt switch in the
open position. |
4. |
Test for infinite resistance
between the signal circuit terminal 1 and the ground terminal 2 at
the B88 seat belt switch. |
⇒ If there is not
infinite resistance
⇒ |
Replace the B88 seat belt switch. |
⇓ If there is
infinite resistance
5. |
B88 seat belt switch in the
closed position. |
6. |
Test for less than 1 Ω
between the signal circuit terminal 1 and the ground terminal 2 at
the B88 seat belt switch. |
⇒ If 1 Ω or
greater
⇒ |
Replace the B88 seat belt switch. |
⇓ If less than 1
Ω
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
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