Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Combination meter / Malfunction in tachometer
Toyota Corolla (E120): Malfunction in tachometer
Wiring diagram

Inspection procedure

- Check output value of ecm.
- Connect the hand–held tester to dlc3.
- Turn the ignition switch to on and push the hand–held tester main switch on.
- Select the data list mode on the hand–held tester.


2 Inspect combination meter assy

(Reference) inspection using oscilloscope
- check the input signal waveform.
- Remove the combination meter assy with connectors still connected.
- Connect the oscilloscope to the terminals c9–19 of combination meter assy and body ground.
- Start engine.
- Check the signal waveform.




3 Check harness and connector(between ecm and combination meter assy)
- Remove the combination meter.
- check the continuity between terminals 5 (tach) of ecm and c9–19 of combination meter connector.
Standard: there is continuity.


Check and replace ecm
Other materials:
Circuit description
The intake air temperature (iat) sensor, mounted on the mass
air flow (maf) sensor, monitors the intake air temperature. The
iat sensor has a thermistor that varies its resistance depending
on the temperature of the intake air. When the air temperature
is low, the resistance in the thermisto ...
Temporarily engaged gear steps selection mode in the D position
To drive in temporary gear steps selection mode, operate the “-” and “+” paddle
shift switches. The gear steps can then be selected by operating the “-” and “+”
paddle shift switches. By selecting gear step using paddle shift switches, you can
control engine braking forces.
1 ...
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) ...


