Suzuki Wagon R Plus RB310, Service Manual

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6E2-38 ENGINE AND EMISSION CONTROL SYSTEM (M13 ENGINE)
Radiator fan control system inspection
System Inspection
Check system for operation referring to “Diag. Flow Table B-7” in
Section 6-2.
If radiator fan fails to operate properly, check relay, radiator fan
and electrical circuit.
Mass air flow (MAF) and intake air temperature (IAT)
sensor on-vehicle inspection
1) Disconnect negative cable at battery.
2) Disconnect MAF and IAT sensor connector.
3) Connect voltmeter to “BLK/RED” wire terminal (2) of MAF
and IAT sensor coupler (1) disconnected and ground.
4) Turn ignition switch ON and check that voltage is battery volt-
age.
If not, check if wire harness is open or connection is poor.
5) Turn ignition switch OFF and connect coupler to MAF and
IAT sensor.
6) Turn ignition switch ON and check MAF signal voltage
between “E22-14” terminal and “E22-32” terminal of ECM
coupler.
MAF signal voltage of MAF and IAT sensor at ignition
switch ON: 0.5 – 1.0 V
7) Start engine and check that voltage is lower than 5 V and it
rises as engine speed increases.
MAF signal reference voltage of MAF and IAT sensor at
specified ldle speed: 1.3 – 1.8 V
8) If check result is not as specified above, cause may lie in
wire harness, coupler connection, MAF and IAT sensor or
ECM.
WARNING:
Keep hands, tools, and clothing away from engine cool-
ing fan to help prevent personal injury. This fan is electric
and can come on whether or not the engine is running.
The fan can start automatically in response to the ECT
sensor with the ignition switch in the “ON” position.
1. ECM
E22-32
E22-14
1