C21" Iat Sensor Circuit Malfunction - Suzuki AN400 Service Manual

"C21" IAT SENSOR CIRCUIT MALFUNCTION

DETECTED CONDITION
Output voltage low or high
(0.20 Sensor voltage < 4.80 V)
(without the above range.)
INSPECTION
Step 1
1) Remove the frame cover. (#7-18)
2) Turn the ignition switch OFF.
3) Check the IAT sensor coupler for loose or poor contacts.
If OK, then measure the IAT sensor voltage at the wire side
coupler.
4) Disconnect the coupler 1 and turn the ignition switch ON.
5) Measure the voltage between B/Bl wire terminal and ground.
6) If OK, then measure the voltage between B/Bl wire terminal
and B/Br wire terminal.
$ IAT sensor voltage: 4.5 – 5.5 V
! 09900-25008: Multi circuit tester set
& Tester knob indication: Voltage (')
Is the voltage OK?
YES Go to Step 2
• Loose or poor contacts on the ECM coupler.
NO • Open or short circuit in the B/Bl wire or B/Br
wire.
( + B/Bl – - Ground)
( + B/Bl – - B/Br)
POSSIBLE CAUSE
• IAT sensor circuit open or short.
• IAT sensor malfunction.
• ECM malfunction.
FI SYSTEM 4-33