Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Cruise control system / Idle signal circuit / Circuit description
Toyota Corolla (E120): Circuit description
When the idle switch is turned on, a signal is sent to the cruise control ecu assy. The cruise control ecu assy uses this signal to correct the discrepancy between the throttle valve position and the actuator position sensor values to enable accurate cruise control at the set speed. If the idle switch is malfunctioning, problem symptoms also occur in the engine, so also inspect the engine.

Wiring diagram

Other materials:
Inspection procedure
Hint:
if dtc p0441 (purge flow), p0446 (vsv for ccv or vsv for pressure
switching valve), p0451, p0452
or p0453 is output with dtc p0442 or p0456 , first troubleshoot
dtc p0441, p0446, p0451, p0452 or p0453. If no malfunction is detected,
troubleshoot dtc
p0442 or p0456 next.
...
Check mode procedure
Hint:
hand–held tester only:
compared to the normal mode, the check mode has more sensing
ability to detect malfunctions. Furthermore, the same diagnostic
items which are detected in the normal mode can also be
detected in the check mode.
1. Check mode procedure(using the hand–held tester) ...
On–vehicle inspection
1. Check cooling fan operation with low temperature (below 83 c (181 f))
Turn the ignition switch on.
check that the cooling fan stops.
Hint:
if not, check the cooling fan relay and water temperature sensor, and check for
separated connector or severed
wire between the cooling fan ...


