Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / ABS with EBD system / Brake warning light circuit
Toyota Corolla (E120): Brake warning light circuit
Other materials:
Circuit description
The p/t squib (lh) circuit consists of the airbag sensor assy center and seat
belt pretensioner (lh).
It causes the srs to deploy when the srs deployment conditions are satisfied.
Dtc b0135/73 is recorded when a short is detected in the p/t squib (lh) circuit.
Wiring diagram
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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.
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Inspection procedure
1 Inspect ecm(+b voltage)
Turn the ignition switch on.
measure the voltage between the terminals of the e4 and
e6 ecm connectors.
Standard:
2 Check harness and connector(ecm – body ground)
Disconnect the e4 ecm connector.
check the resistance between the wire ...


