Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Toyota vehicle intrusion protection system / Horn relay circuit / Circuit description
Toyota Corolla (E120): Circuit description
When the tvip system is transferred from the armed state to the alarm sounding state, the tvip ecu switches on the horn relay so that it can sound the horns. The horn sounds in 0.4 Seconds interval.
Wiring diagram

Other materials:
How to proceed with troubleshooting
1 Vehicle brought in
2 Customer problem analysis check and symptom check
3 Problem symptoms table
Without applicable symptoms, proceed to ”a”
with applicable symptoms, proceed to ”b”
4 Perform troubleshooting in the following method, depending on
malfunction symptom ...
Dynamic radar cruise control
This dynamic radar cruise
control detects the presence
of vehicles ahead,
determines the current vehicle-
to-vehicle distance, and
operates to maintain a suitable
distance from the vehicle
ahead. The desired
vehicle-to-vehicle distance
can be set by operating the
vehicle-to-vehicle distance
switch.
...
Description
When troubleshooting obd ii vehicles, the only difference
from the usual troubleshooting procedure is that you
need to connect the vehicle to the obd ii scan tool complying
with sae j1978 or the hand–held tester, and read
various data output from the vehicle’s ecm.
Obd ii regulation ...


