Suzuki RA410 Manual page 373

6E1-8 ENGINE AND EMISSION CONTROL SYSTEM
CHECK
ENGINE
DIAGNOSIS
The engine and emission control system in this vehicle are con-
trolled by ECM/PCM. ECM/PCM has an On-Board Diagnostic sys-
tem which detects a malfunction in this system.
When diagnosing troubles, be sure to have full understanding of
the outline of ON-BOARD DIAGNOSTIC SYSTEM and each item
in PRECAUTION IN DIAGNOSING TROUBLE and execute diag-
nosis according to ENGINE DIAGNOSIS FLOW TABLE in SEC-
TION 6.
ON-BOARD DIAGNOSTIC SYSTEM
ECM/PCM performs on-board diagnosis (self-diagnosis) on the
system and operates "CHECK ENGINE" light (malfunction indica-
tor lamp) as follows.
Malfunction indicator lamp ("CHECK ENGINE" light) lights when
the ignition switch is turned to ON position (but the engine at
stop) regardless of the condition of engine and emission control
system. This is only to check the malfunction indicator lamp
("CHECK ENGINE" light) bulb and its circuit.
If the areas monitored by ECM/PCM is free from any trouble af-
ter the engine start (while engine is running), malfunction indica-
tor lamp ("CHECK ENGINE" light) turns OFF.
When ECM/PCM detects a trouble which has occurred in the
areas it monitors, malfunction indicator lamp ("CHECK EN-
GINE" light) turns ON while the engine is running to warn the
driver of such occurrence of trouble and at the same time it
stores the exact trouble area in ECM/PCM back-up memory.
PRECAUTIONS IN DIAGNOSING TROUBLES
Before identifying diagnostic trouble code, don't disconnect con-
nectors from ECM/PCM, battery cable from battery, ECM/PCM
ground wire harness from engine. Such disconnection will erase
memorized trouble in ECM/PCM memory.
Be sure to read PRECAUTIONS FOR ELECTRICAL CIRCUIT
SERVICE in SECTION 0A before inspection and observe what
is written there.
ECM/PCM replacement
When substituting a known-good ECM/PCM, check for the fol-
lowing conditions. Neglecting this check may cause damage to
known-good ECM/PCM.
– Resistance value of all relays, actuators is as specified re-
spectively.
– TP sensor and MAP sensor are in good condition and none of
power circuits of these sensors is shorted to ground.