Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Cruise control system / Idle signal circuit
Toyota Corolla (E120): Idle signal circuit
Dtc 51 idle signal circuit
Other materials:
Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the
table below. Use this table to
troubleshoot the problem when a normal code is displayed in the diagnostic
trouble code chart but the problem
is still occurring. Numbers in the table indicate the order in which the
circ ...
Circuit description
The rotary solenoid type idle air control (iac) valve is located
under the throttle body and intake air bypassing the throttle
valve flows into the iac valve through the passage.
In this way the intake air volume bypassing the throttle valve is
regulated, controls the engine speed.
The ...
Inspection
1. Intake air flow meter sub–assy
Inspect the intake air flow meter resistance.
Using an ohmmeter, measure the resistance between
terminals tha and e2.
Resistance:
at –20 c (–4 f) 13.6 To 18.4 KΩ
at 20 c (68 f) 2.21 To 2.69 KΩ
at 60 c (140 f) 0.49 To 0.67 ...


