SPN 158, FMI 4: Voltage Low
Step
Action
Yes
No
1
1. Turn Ignition OFF.
2. Set DVOM to read volts DC.
3. Connect red meter test lead on DVOM to battery positive (+) post.
4. Connect black meter test lead on DVOM to ground.
5. Turn Ignition ON, Engine OFF.
6. Does DVOM read 12+ volts DC?
Go to step 2.
Charge or
replace battery.
2
1. Turn Ignition OFF.
2. Back probe terminal 8 (Violet wire) at the operator panel connector.
3. Connect terminal 8 back probe to red meter test lead on DVOM.
4. Connect black meter test lead on DVOM to ground.
5. Turn Ignition ON, Engine OFF.
6. Does DVOM read 12+ volts DC?
Go to step 3.
Check vehicle or
equipment side
for problems.
3
1. Check condition of 2 amp fuse in the fuse block. Is fuse OK?
Go to step 4.
Replace fuse
and retest.
4
1. Turn Ignition OFF.
2. Back probe terminal J4 (Violet wire) at ECM connector.
3. Connect terminal J4 back probe to red meter test lead on DVOM.
4. Connect black meter test lead on DVOM to ground.
5. Turn Ignition ON, Engine OFF.
6. Does DVOM read 12+ volts DC?
No problem currently exists.
Inspect EFI wire
harness between
the operator panel
connector and terminal
J4 (Violet wire) at
ECM connector.
38
Not for
Reproduction
Summary of Contents for 25E300
Page 1: ...Vanguard EFI Diagnostics and Repair 25E300 REPAIR MANUAL N o t f o r R e p r o d u c t i o n...
Page 18: ...Model 25E300 EFI Component Locations 19 N o t f o r R e p r o d u c t i o n...
Page 26: ...Speed vs Voltage Table 8 27 N o t f o r R e p r o d u c t i o n...
Page 61: ...25E300 Wiring Harness Diagram 62 vanguardpower com N o t f o r R e p r o d u c t i o n...
Page 62: ...63 N o t f o r R e p r o d u c t i o n...
Page 88: ...Model 25E300 Fuel Hose Location and Routing Tankless 89 N o t f o r R e p r o d u c t i o n...
