Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Ignition coil primary/secondary
circuit / Circuit description
Toyota Corolla (E120): Circuit description
Hint
:
- these dtcs indicate a malfunction related to the primary circuit.
- If dtc p0351 is displayed, check the no.1 Ignition coil with igniter circuit.
- If dtc p0352 is displayed, check the no.2 Ignition coil with igniter circuit.
- If dtc p0353 is displayed, check the no.3 Ignition coil with igniter circuit.
- If dtc p0354 is displayed, check the no.4 Ignition coil with igniter circuit.
A direct ignition system (dis) is used on this vehicle. The dis improves the ignition timing accuracy, reduces high–voltage loss, and enhances the overall reliability of the ignition system by eliminating the distributor.
The dis is a 1–cylinder ignition system which ignites one cylinder with one ignition coil. In the 1–cylinder ignition system, the one spark plug is connected to the end of the secondary winding. High voltage generated in the secondary winding is applied directly to the spark plug. The spark of the spark plug passes from the center electrode to the ground electrode.
The ecm determines the ignition timing and outputs the ignition signals (igt) for each cylinder. Using the ignition (igt) signal, the ecm turns on and off the power transistor inside the igniter and this switches on and off the current to the primary coil. When the current flow to the primary coil is cut off, high–voltage is generated in the secondary coil and this voltage is applied to the spark plugs to spark inside the cylinders.
As the ecm cuts the current to the primary coil, the igniter sends back the ignition confirmation (igf) signal for each cylinder ignition to the ecm.

Monitor description

If the ecm does not receive the ignition confirmation signal (igf) after sending the ignition signal (igt), it interprets this as a fault in the igniter and sets a dtc.
Monitor strategy

Typical enabling conditions

Typical malfunction thresholds

Component operating range

Wiring diagram

Other materials:
On–vehicle inspection
1. Inspect w/receiver condenser assy
if a fin of the w/receiver condenser assy is dirty, clean it with
water and dry it with compressor air.
Notice:
do not damage the fin of the w/receiver condenser assy.
if a fin of the w/receiver condenser assy is bent, make it
straig ...
On–vehicle inspection
1. Inspection throttle body idle speed control valve assy
Notice:
it is impossible to check the resister value and the operation
of isc valve by itself, because the isc valve
has an ic circuit inside it, which transforms the duty
signal from the ecm to the derive signal.
After check ...
Air bag sensor front lh
Components
Replacement
Hint: components:
1. Precaution
2. Disconnect battery negative terminal
3. Remove air bag sensor front lh
Disconnect the connector from the airbag sensor front
lh.
remove the 2 bolts and airbag sensor front lh.
4. Inspect air bag sensor front lh
...


