Dtc P0505 Idle Air Control (Iac) Malfunction (Non-Scan Diagnostics) - Briggs & Stratton VANGUARD M490000 Repair Manual

DTC P0505 Idle Air Control (IAC) Malfunction (Non-Scan Diagnostics)

Step
1 1. Disconnect and reconnect IAC and TPS connectors.
2. Turn Ignition ON, Engine OFF.
3. Clear codes.
4. Turn Ignition OFF, and then back ON.
5. Does DTC return?
2 1. Start engine and allow it to warm up for 5 minutes.
2. When engine idle speed is stabilized, use tachometer to record RPM.
3. Is tachometer reading 750-950 RPM?
NOTE: Cold engine temperatures and low battery voltages can cause high engine
idle speeds. For example, at -18° F (-28° C), idle speed can be as high as 1350
RPM, while low battery voltages at normal engine operating temperatures can
cause the engine idle speed to reach 1200 RPM.
3 1. Turn Ignition OFF.
2. Back probe terminal 3 (Pink/Black wire) of TPS connector.
3. Connect terminal 3 back probe to red meter test lead on DVOM.
4. Connect black meter test lead on DVOM to a known good ground.
5. Set DVOM to read volts DC.
6. Start engine and run at idle speed.
7. Does DVOM read 0.5-0.75 volts DC?
4 1. Turn Ignition OFF.
2. Remove IAC from throttle body and inspect for stuck pintel or carbon build up in
IAC port.
3. Are either of these conditions found?
TPS Connector
Action Yes
Go to step 2. Problem corrected.
Look for Go to step 3.
intermittent
conditions.
Go to step 4. Reset TPS.
See TPS Removal/Installation/
Adjustment in SECTION 5 -
REMOVAL/INSTALLATION.
Clean or repair Inspect for intake tract leaks
as necessary. after the throttle body.
Return to step
2 and repeat
test procedure.
No
2
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