Toyota Corolla (E120): Noise occurs
Inspection procedure
1 Check of speaker installation
- Check speaker installation condition.
- Check that each speaker is securely installed.
Standard: malfunction disappear.
Hint
: the radio is equipped with noise prevention system that does not work against the regular use of the radio, thereby excessively large noise cannot occur in the radio. If large noise occurs, check whether or not the earth on the antenna installation part and the proper noise–prevention equipment are all installed, and whether or not the improper wiring is held.

Hint
:
- identify the condition under which the noise occurs, and check the noise filter on the related part.
- Make sure first that there is no noise from outside. Failing to do so makes the noise occurrence source detection impossible and leads to misunderstanding.
- The noise should be removed in descending order of loudness.


Identification of noise source
Other materials:
Circuit description
The vehicle speed sensor circuit is sent to cruise control ecu assy as a
vehicle speed signal. For each rotation
of the shaft, the vehicle speed sensor sends a signal through the combination
meter assembly to the
cruise control ecu assy (see the following chart). The cruise control ecu assy
...
How to proceed with troubleshooting
The hand–held tester can be used at step 3, 4, 6, 9.
1 Vehicle brought to workshop
2 Customer problem analysis
3 Connect the obd ii scan tool or hand–held tester to dlc3
4 Check and clear dtc and freeze frame data
5 Visual inspection
6 Setting the check mode diagnosis
7 Proble ...
Headlamp dimmer switch assy
Replacement
1. Remove steering column cover lwr
Remove 3 screws and steering column cover lwr.
2. Remove headlamp dimmer switch assy
Disconnect the connector.
release the claw and pull out the head light dimmer
switch assy.
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