Toyota 2GR-FE Manual page 448

ES–292
DTC
DTC
DESCRIPTION
The stop light switch is a duplex system that transmits two signals: STP and ST1-. These two signals are
used by the ECM to monitor whether or not the brake system is working properly. If the signals, which
indicate the brake pedal is being depressed and released, are detected simultaneously, the ECM
interprets this as a malfunction in the stop light switch and sets the DTC.
HINT:
The normal conditions are as shown in the table below. The signals can be read using an intelligent tester.
Signal
STP
ES
ST1-
DTC No.
P0504
P0724
MONITOR DESCRIPTION
This DTC indicates that the stop light switch remains on. When the stop light switch remains ON during
"stop and go" driving, the ECM interprets this as a fault in the stop light switch and the MIL comes on and
the ECM stores the DTC. The vehicle must stop (less than 2 mph (3 km/h)) and go (19 mph (30 km/h) or
more) 5 times in two driving cycles in order to detect a malfunction.
MONITOR STRATEGY
Related DTCs
Required sensors/Components
Frequency of operation
Duration
MIL operation
Sequence of operation
TYPICAL ENABLING CONDITIONS
The monitor will run whenever this DTC is not present
Engine switch
Starter
Battery voltage
GO (Vehicle speed is 18.65 mph (30 km/h) or more)
STOP (Vehicle speed is less than 1.86 mph (3 km/h))
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
P0504 Brake Switch "A" / "B" Correlation
P0724 Brake Switch "B" Circuit High
Brake Pedal Released
OFF
ON
DTC Detection Condition
Conditions (a), (b) and (c) continue for 0.5 seconds or
more
(1 trip detection logic):
(a) Ignition switch on (IG)
(b) Brake pedal released
(c) STP signal OFF when ST1- signal OFF
The stop light switch remains ON even when the
vehicle is driven in a STOP (less than 2 mph (3 km/h))
and GO (19 mph (30 km/h) or more) fashion 5 times. (2
trip detection logic)
In Transition
ON
ON
• Short in stop light switch signal circuit
• Stop light switch
• ECM
• Short in stop light switch signal circuit
• Stop light switch
• ECM
P0724: Stop light switch/Rationality
Stop light switch, Vehicle speed sensor
Continuous
GO and STOP 5 times
2 driving cycles
None
None
ON
OFF
8 V or more
Once
Once
Brake Pedal Depressed
ON
OFF
Trouble Area