Suzuki Engine 2002 GRAND VITARA SQ625 - Page 223

6-1-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H25 ENGINE)
Fig. for Step 2, 3
4 HO2S Heater Control Circuit check :
1) With ignition switch OFF, install HO2S
heater relay.
2) With ignition switch ON leaving engine OFF,
check voltage between C51-3-17 and
ground.
Is the voltage 10 – 14 V?
Substitute a known-good
ECM (PCM) and recheck.
Faulty HO2S heater relay
or “WHT/BLK” wire
shorted to ground circuit.
If OK, substitute a known-
good ECM (PCM) and
recheck.
Step Action Yes No
1
2
“BLU/WHT”
“BLU”
“BLK/WHT”
“BLK”