Suzuki Wagon R Manual page 3209

6E2-32 ENGINE AND EMISSION CONTROL SYSTEM (M13 ENGINE)
Engine coolant temperature sensor (ECT sensor)
inspection
Immerse temperature sensing part of ECT sensor (1) in water (or
ice) and measure resistance between terminals while heating
water gradually.
If measured resistance does not show such characteristic as
shown in the graph, replace ECT sensor (1).
Heated oxygen sensor (HO2S-1 and HO2S-2) heater
on-vehicle inspection
1) Disconnect sensor connector.
2) Using ohmmeter, measure resistance between terminals
"V " and "GND" of sensor connector.
B
If found faulty, replace oxygen sensor.
NOTE:
Temperature of sensor affects resistance value largely.
Make sure that sensor heater is at correct temperature.
Resistance of oxygen sensor heater
HO2S–1: 5.0 – 6.4 Ω
HO2S–2: 11.7 – 14.3
1. Viewed from terminal side
3) Connect sensor connector securely.
at 20°C (68°F)
Ω at 20°C (68°F)