OVERCRANK

Possible Causes

• •Active shutdown fault (High Engine Temperature, Low Oil Pressure, Overcrank, or Overspeed)
• •Bad connections on Cycle Cranker module J4
• •Battery connected incorrectly or abnormal voltage
• •Blown fuse F1
• •Defective Engine Monitor module J5
• •Defective R-S-R switch S15
• •Defective starter
• •Dirty K12 relay contacts or defective K12 relay
• •Dirty K14 relay contacts or defective K14 relay
• •Dirty ignition relay K12 socket connection or open K12 coil
• •Engine speed reaches approximately 2100 r/min (overspeed condition)
• •Engine temperature reaches 215°F (102°C)
• •Failure to start after the 75-second cranking period
• •Faulty Cycle Cranker module J4
• •Faulty K13 start solenoid relay
• •High Engine Temperature shutdown
• •Ignition relay K12 fails to energize
• •Incorrect battery connection or abnormal voltage
• •K13 pin 1 not grounded
• •Low engine temperature
• •Oil pressure drops to 14 psi (97 kPa)
• •Open K12 ignition relay coil or dirty K12 relay socket connection
• •Open-circuit starter coil or poor wiring between TB11 terminal 22 and starter
• •Start solenoid K13 fails to energize

Suggested Actions

1. 1Check Start-Disconnect module J3 and Reset
2. 2Check fuse F1
3. 3Check if K13 pin 1 is grounded
4. 4Check if ignition relay K12 energizes (See Test Procedure [A])
5. 5Check wiring between TB11 terminal 22 and starter
6. 6Clean K12 relay contacts or replace K12 relay
7. 7Clean K12 relay contacts or replace relay and check wiring (See Test Procedure [D])
8. 8Clean K14 relay contacts 1 & 7 and check wiring, or replace K14 if necessary (See Test Procedure [D])
9. 9Clean K14 relay contacts 1 h 7, check wiring, and replace K14 if necessary (See Test Procedure [D])
10. 10Clean ignition relay K12 socket connection or replace K12
11. 11Clean relay K12 socket connection
12. 12Jumper B+ at center terminal of R-S-R switch to terminal B of K12, check if engine cranks, and replace Engine Monitor module J5 (See Test Procedure [J])
13. 13Measure B+ voltage at starter coil terminal (See Test Procedure [C])
14. 14Perform High Engine Temperature fault checks (See block 1 on page 20)
15. 15Perform Low Oil Pressure fault checks (See block 2 on page 20)
16. 16Perform Overcrank fault checks (See block 3 on page 20)
17. 17Perform Overspeed fault checks (See block 4 on page 20)
18. 18Perform jumper test (jumper B+ at center terminal of R-S-R switch to terminal B of K12) and see Test Procedure [J]
19. 19Remove jumper and replace Engine Monitor module J5
20. 20Replace Cycle Cranker module J4 and check connections
21. 21Replace K13 start solenoid relay
22. 22Replace defective R-S-R switch S15
23. 23Replace starter
24. 24Verify battery connection and voltage (See Test Procedure [B])

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