| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM100000001HAPM |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: THEFT DETERRENT / KEYLESS ENTRY: THEFT DETERRENT SYSTEM (for HV Model): Horn Circuit; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022] | ||
|
Horn Circuit |
DESCRIPTION
When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU (multiplex network body ECU) transmits a signal to cause the horn to sound at intervals of 0.4 seconds.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
-
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
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![2020 MY Corolla Corolla HV [01/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION](/t3Portal/stylegraphics/info.gif)
- Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
|
1. |
INSPECT HORN |
(a) Press the horn switch and check if the horn sounds.
|
Result |
Proceed to |
|---|---|
|
Horns sound |
A |
|
Horns do not sound |
B |
| B |
|
|
|
2. |
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
(a) Remove the main body ECU (multiplex network body ECU).
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|
*a |
Component without harness connected (Instrument Panel Junction Block Assembly) |
- |
- |
(b) Disconnect the 4B instrument panel junction block assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
4B-27 - MB-28 (HORN) |
Always |
Below 1 Ω |
| OK |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
|
| NG |
|
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
|
|
|