Suzuki GRAND VITARA Owner's Manual page 208

1A-153 Engine General Information and Diagnosis:
DTC Troubleshooting
NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
"Precautions For DTC Troubleshooting: ".
Step
1 Was "Engine and Emission Control System Check"
performed?
2 Stop lamp (brake pedal) switch check
1) Check stop lamp (brake pedal) switch referring to "Stop
(Brake) Lamp Switch Inspection: in Section 9B".
Is it in good condition?
3 Stop lamp (brake pedal) switch power circuit check
1) Disconnect connector from stop lamp (brake pedal)
switch connector with ignition switch turned OFF.
2) Check for proper connection to switch connector.
3) If connection are OK, measure voltage between each
"BLU/BLK" wire terminal and "GRN" wire terminal of stop
lamp switch connector and vehicle body ground with
ignition switch tuned ON.
Is each measured voltage 10 – 14 V?
4 Stop lamp (brake pedal) switch signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Check for proper connection of each switch circuit
terminal to ECM connector.
3) If connections are OK, check stop lamp switch circuit for
the following.
• Resistance of each "YEL/GRN" wire terminal and
"GRN/WHT" wire terminal of stop lamp (brake pedal)
switch between stop lamp (brake pedal) switch
connector and ECM connector is less than 1 Ω
(continuity check)
• Resistance between "YEL/GRN" wire terminal and
"GRN/WHT" wire terminal of stop lamp (brake pedal)
switch connector are infinity (no continuity check)
• Resistance between each "YEL/GRN" wire terminal
and "GRN/WHT" wire terminal of stop lamp (brake
pedal) switch connector and vehicle body ground is
infinity (ground short check)
• Voltage of between each "YEL/GRN" wire terminal
and "GRN/WHT" wire terminal of stop lamp (brake
pedal) switch connector and vehicle body ground is 0
V with ignition switch tuned ON (power short check)
Is it in good condition?
Action Yes
Go to Step 2.
Go to Step 3.
Go to Step 4.
Substitute a known-
good ECM and recheck.
No
Go to "Engine and
Emission Control
System Check: ".
Replace stop lamp
(brake pedal) switch.
Check related fuse and
repair defective circuit.
Repair or replace
defective wire.