Suzuki Wagon R Plus RB310, Service Manual

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6-2-102 ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE)
1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Increase vehicle speed to 60 – 80 km/h (37 – 50 mile/h) at 5th gear or D range.
5) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 4 sec. or
more), then stop vehicle and run engine at idle speed for 6 sec. or more.
6) Repeat Step 4).
7) Keep above vehicle speed for 8 min. or more. (Throttle valve opening is kept constant in this Step.)
8) Repeat Step 5).
9) Check DTC and pending DTC.
Troubleshooting
Step Action Yes No
1 Was “Engine and Emission Control System
Check” performed? Go to Step 2. Go to “Engine and Emis-
sion Control System
Check” in this section.
2 Is there DTC(s) other than fuel system (DTC
P0171/P0172) and HO2S–2 (DTC P0134)? Go to applicable DTC
diag. flow table. Go to Step 3.
3 Check HO2S–2 and its circuit.
1) Connect scan tool to DLC with ignition
switch turned OFF.
2) Warm up engine to normal operating tem-
perature and keep it at 2000 r/min. for 60
sec.
3) Repeat racing engine (Repeat depressing
accelerator pedal 5 to 6 times continuously
and take foot off from pedal to enrich and
enlean A/F mixture).
Does HO2S–2 output voltage indicate deflect
between over 0.35 V and below 0.25 V?
Go to DTC P0171 and
P0172 diag. flow table
(Fuel System Check). Go to Step 4.
4 Check HO2S–2 sensor ground.
1) Disconnect connector from HO2S–2 sen-
sor with ignition switch turned OFF.
2) Check for proper connection to HO2S–2
sensor connector at “BLU/RED”, “BLU”,
“BRN/WHT” and “BLK/WHT” wire terminals.
3) If wire and connection are OK, check there
is continuity between “BRN/WHT” wire ter-
minal of HO2S–2 sensor connector and
engine ground.
Is it continuity?
Go to Step 5. “BRN/WHT” wire open cir-
cuit.
Poor “E22-28” terminal
connection.
Faulty ECM ground.
If they are OK, substitute
a known-good ECM and
recheck.
5 Check HO2S–2 sensor ground.
1) With ignition switch turn ON, check voltage
between “BRN/WHT” wire terminal of
HO2S–2 sensor connector and engine
ground.
Is voltage about 0.1 V or less?
Go to Step 6. “BRN/WHT” wire high
resistance circuit.
Poor “E22-28” terminal
connection.
Faulty ECM ground.
If they are OK, substitute
a known-good ECM and
recheck.