Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Toyota vehicle intrusion protection system / Horn relay circuit / Inspection procedure
Toyota Corolla (E120): Inspection procedure
1 Check low pitched horn assy

- Connect the positive (+) lead from the battery to the terminal and negative (–) lead to the horn body, and check that the horn blows.


2 Check relay (marking: horn)

- Remove the relay from the engine room j/b.
- check the horn relay continuity, as shown in the illustration and table.
Standard:



3 Check wire harness (tvip ecu engine room j/b)

- Remove the horn relay from the engine room j/b.
- check the continuity between the terminals of the tvip ecu and engine room j/b connectors, as shown in the illustration and table.
Standard:

*: Horn relay terminal


4 Check wire harness (engine room j/b horn)

- Check the continuity between the terminals of the engine room j/b and horn connectors, as shown in the illustration and table.
Standard:

*: Horn relay terminal.


Check and replace tvip ecu
Other materials:
Dtc check/clear
1. Dtc check (normal mode)
Notice:
hand–held tester only:
when the diagnostic system is switched from the normal
mode to the check mode, all the dtcs and freeze frame
data recorded in the normal mode will be erased. So before
switching modes, always check the dtcs and freeze frame
data, and ...
Electronic control
Removal and installation of battery terminal
before performing electrical work, disconnect the
battery negative (–) terminal cable beforehand so
as to prevent burnt–out damage by short.
When disconnecting and installing the terminal
cable, turn the ignition switch an ...
Inspection procedure
Hint:
if different dtcs related to different systems that have terminal e2
as the ground terminal are output
simultaneously, terminal e2 may be open.
If dtc p0441 (purge flow), p0446 (vsv for ccv), p0451, p0452 or p0453
(evaporative pressure
sensor) is output with dtc p0442 or p0456, ...


