Suzuki Wagon R Plus RB310 Service Manual page 317

6-2-142 ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE)
Troubleshooting
Step
1 Was "Engine and Emission Control System
Check" performed?
2 Check MAP sensor and its circuit.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON.
3) Check intake manifold pressure.
Is it 146 kPa (43.1 in.Hg) or 0 kPa (0 in.Hg)?
3 Check MAP sensor power supply voltage.
1) Disconnect connector from MAP sensor
with ignition switch tuned OFF.
2) Check for proper connection of MAP sensor
at "WHT/GRN", "LT GRN/RED" and "BRN/
WHT" wire terminals.
3) Turn ON ignition switch, measure voltage
between engine ground and "WHT/GRN"
wire terminal. See Fig. 1.
Is voltage 4 – 5 V?
4 Check MAP sensor power supply voltage.
1) Disconnect connectors from ECM with igni-
tion switch turned OFF.
2) Remove ECM from vehicle body and then
connect connectors to ECM.
3) Turn ON ignition switch, measure voltage
between vehicle body ground and "E22-8"
terminal.
Is voltage 4 – 5 V?
5 Check MAP sensor ground circuit.
1) Measure resistance between "BRN/WHT"
wire terminal in MAP sensor harness con-
nector and engine ground.
Is resistance below 5
6 Check ground circuit.
1) Disconnect connectors from ECM with igni-
tion switch turned OFF.
2) Remove ECM from vehicle body and con-
nect connectors to ECM.
3) Measure resistance between "E22-28" ter-
minal and vehicle body ground.
Is resistance below 5
Action
Ω
?
Ω
?
Yes
Go to Step 2.
Go to Step 3.
Go to Step 5.
"WHT/GRN" wire in open
circuit.
Go to Step 7.
"BRN/WHT" wire in open
or high resistance circuit.
No
Go to "Engine and Emis-
sion Control System
Check".
Intermittent trouble.
Check for intermittent
referring to "Intermittent
and Poor Connection
Inspection" in Section 0A.
If OK, go to Step 8.
Go to Step 4.
"WHT/GRN" wire shorted
to other circuit.
If wires are OK, substi-
tute a known-good ECM
and recheck.
Go to Step 6.
ECM grounds "E23-1"
and/or "E23-2" circuit in
open or high resistance.
If wires are OK, substi-
tute a known-good ECM
and recheck.