Suzuki 2000 Grand Vitara SQ416, Service Manual

Page: 231 / 729

YH4
GRAND
VITARA
6-1-120 ENGINE (H25 ENGINE)
TERMINAL ARRANGEMENT OF ECM (PCM) COUPLER (VIEWED FROM HARNESS SIDE)
DTC P1510 ECM BACK-UP POWER SUPPLY MALFUNCTION
WIRING DIAGRAM
CIRCUIT DESCRIPTION
Battery voltage is translated to 5 V in ECM (PCM) back-up circuit. The voltage is supplied to keep DTC memory,
values that ECM (PCM) has learned to control engine, etc. in ECM (PCM) even when ignition switch is turned OFF.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITION TROUBLE AREA
Back-up circuit voltage is out of specification. Battery voltage supply circuit
ECM (PCM)
DTC CONFIRMATION PROCEDURE
NOTE:
Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCE-
DURE.
Intake air temperature: between – 14 C and 70 C (6.8 F and 158 F)
Atmospheric pressure: higher than 560 mmHg (Altitude: lower than 2790 m (9150 ft))
(1) With ignition switch OFF, connect scan tool.
(2) Turn ON ignition switch and clear DTC by using scan tool if any.
(3) Start engine and run it for 10 sec.
(4) Check DTC by using scan tool.
DTC TROUBLESHOOTING
STEP ACTION YES NO
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE
DIAG. FLOW
TABLE”.
2 Battery Voltage Supply Circuit check:
(1) Remove ECM (PCM) cover.
(2) While engine running, check voltage between
E61-35 and ground.
Is voltage 10 – 14 V?
Intermittent trouble.
If OK, substitute a
known-good ECM
(PCM) and recheck. Fuse 17 is blown or
faulty “W” wire.