6E1-28
ENGINE AND EMISSION CONTROL SYSTEM
CODE NO.18 (P0110) IAT SENSOR CIRCUIT
(SIGNAL VOLTAGE HIGH OR LOW)
1. ECM
2. IAT sensor
3. IAT sensor coupler
4. To other sensors
NOTE:
When Code No.11 (P0105), 13 (P0120), 18 (P0110) and
19 (P0115) are indicated together, it is possible that
“B/G” wire is open or “C52-9” terminal connections
are poor.
STEP
ACTION
YES
NO
1
1) Disconnect IAT sensor coupler with ignition
switch OFF.
2) Check voltage between “Lg/W” wire termi-
nal of IAT sensor coupler and ground with
ignition switch ON.
Is voltage about 4 – 5 V?
Go to Step 2.
“Lg/W” wire open or short.
Poor “E33-214” connection.
2
1) Connect IAT sensor coupler terminals using
service wire.
2) Check voltage between “Lg/W” wire termi-
nal of IAT sensor coupler and ground with
ignition switch ON.
Is voltage 0.15 V or less?
Go to Step 3.
“B/G” wire open or poor
“E34-22” connection.
If wire and connection are OK,
substitute a known-good ECM
and recheck.
3
1) Perform IAT SENSOR INSPECTION in this
section.
Is IAT sensor in good condition?
Poor connection of IAT
sensor coupler termi-
nals.
If connection is OK,
substitute a known-
good ECM and re-
check.
Faulty IAT sensor.
Fig. for STEP 1
Fig. for STEP 2
1. IAT sensor coupler disconnected
2. Engine ground
1. IAT sensor coupler disconnected
2. Service wire
3. Engine ground
NOTE:
Upon completion of inspection and repair work, perform DTC Confirmation Procedure, referring to page
6E1-30 to confirm that the trouble has been corrected.
