Toyota Corolla (E120): Fail–safe chart
If any of the following codes is recorded, the ecm enters the fail–safe mode.

Check for intermittent problems
Hand–held tester only:
by putting the vehicle’s ecm in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic, and the sensitivity to detect faults is increased. This makes it easier to detect intermittent problems.
- Clear the dtcs .
- set the check mode .
- perform a simulation test .
- check the connector and terminal .
- wiggle the harness and connector
Other materials:
Inspection procedure
1 Check p/t squib(lh) circuit(airbag sensor assy center – front seat
outer belt assy lh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the seat belt pretensio ...
On–vehicle inspection
1. Inspect refrigerant pressure with manifold gauge set
this is a method in witch the trouble is located by using
a manifold gauge set. Read the manifold gauge pressure
when the these conditions are established.
Test conditions:
temperature at the air inlet with the switch set
...
Circuit description
The seat belt buckle switch (lh) circuit consists of the airbag sensor assy
center and front seat inner belt
assy (lh).
Dtc b0126/b0127/27 is recorded when a malfunction is detected in the seat belt
buckle switch (lh) circuit.
Wiring diagram
...


