Trouble diagnosis for unusual pressure
Diagnose using a manifold gauge whenever system’s high and/or low side pressure(s) is/are unusual. The marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Refer to above table (Ambient air temperature-to-operating pressure table) since the standard (usual) pressure, however, differs from vehicle to vehicle.
Symptom table


Heater and air conditioning system symptoms
NoiseStrg branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the steering angle sensor for
damage, bend and loose connection
(unit side and connector side).
Is the inspection result ...
Illumination control switch signal circuit
Diagnosis procedure
Regarding wiring diagram information, refer to mwi-28, "wiring diagram".
1.Check combination meter input signal
Turn ignition switch on.
Check voltage between the following terminals of the illumination
control switch.
Is the inspection result normal?
...
General Precautions
Always use a 12 volt battery as power source.
Do not attempt to disconnect battery cables while engine is
running.
Before connecting or disconnecting the ECM harness connector,
turn ignition switch OFF and disconnect negative battery
cable. Failure to do so may damage the ECM because
...