Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Supplemental restraint system / Source voltage drop / Source voltage drop
Toyota Corolla (E120): Source voltage drop
The srs is equipped with a voltage–increase circuit (dc–dc converter) in the airbag sensor assy center in case the source voltage drops.
When the battery voltage drops, the voltage–increase circuit (dc–dc converter) functions to increase the voltage of the srs to normal voltage.
The diagnosis system malfunction display for this circuit is different from other circuits that is when the srs warning light remains lit up and the dtc is a normal code, source voltage drop is indicated.
Malfunction in this circuit is not recorded in the airbag sensor assy center, and the source voltage returns to normal, the srs warning light automatically goes off.
Wiring diagram
Other materials:
Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...
Inspection procedure
1 Check operation(stop lamp swtich assy)
Check that the stop light comes on when the brake pedal is depressed,
and turns off when the brake
pedal is released.
2 Input signal check
See input signal check on page 05–745.
check the indicator light when the brake pedal ...
Overhaul
Hint:
overhaul the rh side by the same procedures with lh side.
1. Remove rear wheel
2. Drain brake fluid
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
3. Remove rear brake drum sub–assy
Release the parking brake lever, and remove t ...