Suzuki SY413 Service Manual page 2681

6-1-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS (G13/G16 ENGINE WITH WU TWC)
DTC P0400
INSPECTION
STEP
1 Was "ENGINE DIAG. FLOW TABLE" performed?
2 EGR Valve Operation Check:
1) With ignition switch OFF, install SUZUKI scan
tool.
2) Check EGR system referring to Section 6E2.
Is it in good condition?
3 MAP Sensor Check:
1) Check MAP sensor for performance referring to
Section 6E2.
Is check result satisfactory?
4 EGR Valve Power Supply Circuit Check:
1) With ignition switch OFF, disconnect EGR valve
coupler.
2) With ignition switch ON, check voltage between
C15-2 and ground, C15-5 and ground.
Is each voltage 10 – 14 V?
5 EGR Valve Stepper Motor Coil Circuit Check:
1) With ignition switch OFF, connect EGR valve
coupler and disconnect ECM (PCM) couplers.
2) Check resistance between E92-5 and C21-17,
C21-18, C21-28, C21-29.
Is each resistance 20 – 24 W at 205C, 685F?
6 MAP Sensor Check:
1) Check MAP sensor for performance referring to
MAP SENSOR INDIVIDUAL CHECK in Diag.
FLOW TABLE P0105.
Is check result satisfactory?
Fig.1 for Step 4
1. EGR valve coupler
ACTION YES
Go to Step 2.
Go to Step 3.
Intermittent trouble or
faulty ECM (PCM).
Check for intermittent
referring to "Intermittent
and Poor Connection" in
Section 0A.
Go to Step 5.
Go to Step 6.
EGR passage clogged
or EGR valve malfunc-
tion.
If all above are OK, in-
termittent trouble or
faulty ECM (PCM).
Check for intermittent
referring to "Intermittent
and Poor Connection" in
Section 0A.
NO
Go to "ENGINE DIAG.
FLOW TABLE".
Go to Step 4.
Repair or replace.
Faulty "R/B" wire.
Faulty "R/W", "R",
"R/Bl", "R/Y" wire or
EGR valve.
Repair or replace.