Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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6-1-60 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H25 ENGINE)
TROUBLESHOOTING
Step Action Yes No
1 Main Relay Operating Sound check :
Is operating sound of main relay heard at igni-
tion switch ON? Go to Step 5. Go to Step 2.
2 Fuse check :
Is main fuse in good condition? Go to Step 3. Check for short in circuits
connected to this fuse.
3 Main Relay check :
1) Turn OFF ignition switch and remove main
relay.
2) Check for proper connection to main relay at
“BLK/RED” wire terminal and “BLU” wire
terminal.
3) If OK, check main relay for resistance and
operation referring to “Main Relay” in Sec-
tion 6E2.
Is check result satisfactory?
Go to Step 4. Replace main relay.
4 ECM (PCM) Power Circuit check :
1) Turn OFF ignition switch, disconnect con-
nectors from ECM (PCM) and install main
relay.
2) Check for proper connection to ECM (PCM)
at terminals C51-2-3, 20, 21 and E61-8.
3) If OK, then measure voltage between termi-
nal C51-2-3 and ground, E61-8 and ground
with ignition switch ON.
Is each voltage 10 – 14 V?
Go to Step 5. “BLK/WHT”, “BLU” or
“BLK/RED” circuit open.
5 ECM Power Circuit check :
1) Using service wire, ground terminal E61-8
and measure voltage between terminal
C51-2-20 and ground at ignition switch ON.
Is it 10 – 14 V?
Check ground circuits
“BLK/GRN” and “BLK/
BLU” for open.
If OK, then substitute a
known-good ECM (PCM)
and recheck. Go to Step 6.
6 Is operating sound of main relay heard in Step
1? Go to Step 7. “BLK/RED” or “BLU” wire
open.
7 Main Relay check :
1) Check main relay according to procedure in
Step 3.
Is main relay in good condition?
“BLK/RED” or “BLU” wire
open. Replace main relay.