Troubleshooting Harley Davidson Golf Cart 1969-70 DEC Wiring


The final two years of the DEC model changed the headlight and taillight options, plus a few 16 gauge wire configuration changes.

Troubleshooting the DEC Harley Davidson golf cart? The following charts and tables will save you hours of online searching and help to pinpoint solutions to the problems this 50-year old cart may present.

Tools needed for troubleshooting include:

  • A multimeter or voltmeter
  • A 1/2” size wrench
  • Electrical tape
  • Safety glasses

Wiring Diagrams

1969-70 Model DEC Control Circuit Wiring Diagram for 16 Gauge Wire

1969-70 Model DEC Heavy Cable Diagram

Charging

  • Key switch –  Off
  • Speed Switch –  at resting stop
  • Solenoid “A” Open – Voltage not applied to small terminals
  • Solenoid “B” Open – Voltage not applied to small terminals
  • Solenoid “C” Open – Voltage not applied to small terminals
  • Solenoid “F” Open – Voltage not applied to small terminals – Bottom  terminals closed
  • Solenoid “R” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Voltage to Motor – None
  • Voltage across A1 and A2 – None
  • Motor Diodes – None
  • Speed Switch Diode – None
  • Time Delay – Open
  • Micro Switch – NO Open NC Closed

First Speed

  • Key switch –  Forward
  • Speed Switch –  Contact #3
  • Solenoid “A” Open – Voltage not applied to small terminals
  • Solenoid “B” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “C” Open – Voltage not applied to small terminals
  • Solenoid “F” Closed – Voltage applied to small terminals, continuity across large terminals – Bottom  terminals open
  • Solenoid “R” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Voltage to Motor – 18-volts through the Resistor
  • Voltage across A1 and A2 – 12-volts
  • Left Motor Diode – Current flowing from Solenoid “A” to Solenoid “B”
  • Right Motor Diode – Current flowing from Solenoid “C” to Solenoid “A”
  • Speed Switch Diode – Blocks current from Speed Switch  fourth Contact
  • Time Delay – Open
  • Micro Switch – Open

Second Speed

  • Key switch –  Forward
  • Speed Switch –  Contact #4 Micro Switch not depressed yet
  • Solenoid “A” Open – Voltage not applied to small terminals
  • Solenoid “B” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “C” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “F” Closed – Voltage applied to small terminals, continuity across large terminals – Bottom  terminals open
  • Solenoid “R” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Voltage to Motor – 18-volts bypassing the Resistor
  • Voltage across A1 and A2 – 15.5-volts to 16.5-volts
  • Left Motor Diode – Current flowing from Solenoid “A” to Solenoid “B”
  • Right Motor Diode – Current flowing from Solenoid “C” to Solenoid “A”
  • Speed Switch Diode – Allows current from Speed Switch to third Speed Switch Contact and on to Solenoid  “B” and “F”
  • Time Delay – Open
  • Micro Switch – not activated but allowing current to pass to power Solenoid “C”

Third Speed

  • Key switch –  Forward
  • Speed Switch –  Contact #4 Micro Switch has depressed
  • Solenoid “A”  Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “B” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “C” Open – Voltage not applied to small terminals
  • Solenoid “F” Closed – Voltage applied to small terminals, continuity across large terminals – Bottom  terminals open
  • Solenoid “R” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Voltage to Motor – 36-volts through the Resistor
  • Voltage across A1 and A2 -30.5-volts to 31.5-volts
  • Left Motor Diode – Blocking current flowing from Solenoid “A” to Solenoid “C”
  • Right Motor Diode – Blocking current flowing from Solenoid “B” to Solenoid “A”
  • Speed Switch Diode – Allows current from Speed Switch to third Speed Switch Contact and on to Solenoid  “B” and “F”
  • Time Delay – Actuated and powering Solenoid “C” after 1.8 seconds
  • Micro Switch – Activated and powering Solenoid “A” and Time Delay

Fourth Speed

  • Key switch –  Forward
  • Speed Switch –  Contact #4 Micro Switch has depressed
  • Solenoid “A”  Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “B” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “C” Closed – Voltage applied to small terminals, continuity across large terminals
  • Solenoid “F” Closed – Voltage applied to small terminals, continuity across large terminals – Bottom  terminals open
  • Solenoid “R” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Voltage to Motor – 36-volts bypassing the Resistor
  • Voltage across A1 and A2 -33.5-volts to 34.5-volts
  • Left Motor Diode – Blocking current flowing from Solenoid “A” to Solenoid “C”
  • Right Motor Diode – Blocking current flowing from Solenoid “B” to Solenoid “A”
  • Speed Switch Diode – Allows current from Speed Switch to third Speed Switch Contact and on to Solenoid  “B” and “F”
  • Time Delay – Actuated and powering Solenoid “C” 
  • Micro Switch – Activated and powering Solenoid “A” and Time Delay

Reverse (Fourth Speed Shown)

  • Key switch –  Reverse
  • Speed Switch –  Same as Forward Speeds
  • Solenoid “A”  –  Same as Forward Speeds
  • Solenoid “B” – Same as Forward Speeds
  • Solenoid “C”  – Same as Forward Speeds
  • Solenoid “F” Open – Voltage not applied to small terminals – Bottom terminals closed
  • Solenoid “R” Closed – Voltage applied to small terminals, continuity across large terminals – Bottom terminals open
  • Voltage to Motor – Same as Forward Speeds
  • Voltage across A1 and A2 -Same as Forward Speeds
  • Left Motor Diode – Same as Forward Speeds
  • Right Motor Diode – Same as Forward Speeds
  • Speed Switch Diode – Same as Forward Speeds
  • Time Delay – Same as Forward Speeds 
  • Micro Switch – Same as Forward Speeds

Solenoid Arrangement

Solenoid Arrangement For Harley Davidson Golf Cart DE 1967-71

Numbering Key for 1969 – 1970 Diagrams

  1. Key Switch – 3 wires (Green, Blue, Yellow) For terminals 2, 3, and  4
  2. Key Switch Terminal – Green wire to Speed Switch Connection 11
  3. Key Switch Terminal – Blue wire to Speed Switch Connection 12
  4. Key Switch Terminal – Yellow wire to Speed Selector Switch 13
  5. Speed Switch (Contains Terminals 6, 7, 8, 9, 10, 11, 12, 13 and 14)
  6. Speed Switch Terminal – White wire to Terminal 15 on Switch Arm (2), Black wire to Solenoid Terminal A1, Black wire to Circuit Breaker 27 – 4 wires
  7. Speed Switch Terminal – Black wire to Solenoid Terminal A4
  8. Speed Switch Terminal – Red wire to Micro Switch NO terminal, Red wire to Solenoid Terminal A2
  9. Speed Switch Terminal – Orange wire to Time Delay Tube Pin 5, Diode connected to Speed Switch Terminal 10
  10. Speed Switch Terminal – Diode to Key Switch Terminal 9, Black wire to Solenoid Terminal C2, and Black wire to Micro Switch NC Terminal
  11. Speed Switch Terminal – Green wire to Key Switch Terminal  2, and Green wire to Solenoid Terminal R2
  12. Speed Switch Terminal – Blue wire to Solenoid Terminal F2, Blue wire to Key Switch Terminal 3
  13. Speed Switch Terminal – Yellow wire to Key Switch Terminal  4, Diode to Speed Switch Terminal 14
  14. Speed Switch Terminal – White wire to Micro Switch Common, Diode to Speed Switch Terminal 13
  15. Speed Switch Wiper Arm – White wire (2) to Speed Switch Terminal 6
  16. Micro Switch – White wire to Speed Switch Terminal 14, Red wire to Speed Switch Terminal 8, Black wire to Speed Switch Terminal 10
  17. Diode (2)
  18. Charger Connection Plug – Negative Terminal 1 Black wire to Left Motor Diode, Red wire to Right Motor Diode
  19. Solenoids A, B, and C
    Solenoid A 
    A1 – Black wire to Speed Switch Terminal 6
    A2 – Red wire to Time Delay Tube pin #8, Red wire to Speed Switch Terminal 8
    A3 – White wire to Time Delay Tube Pin # 2, White wire to Solenoid Terminal B3
    A4 – Black wire to Left Motor Diode, Black Wire to Circuit Breaker 27, Black wire to Speed Switch Terminal 7
    Solenoid B
    B1 – Copper Strap to  Solenoid Terminal F1
    B2 – Black wire to Solenoid Terminal F3
    B3 – White wire to Solenoid Terminal A3, White wire to Solenoid  Terminal C3
    B4 – Black wire to Right Motor  Diode 22, Black wire  to Battery Positive Post
    Solenoid C
    C1 – Black Wire to Battery Negative Post, Black wire to Resistor 26, Black wire to Left Motor Diode 21
    C2 – Black wire to Speed Switch Terminal 10
    C3 – White wire to Left Motor  Diode 21, White wire to Solenoid Terminal B3
    C4 – Black wire to Resistor 26,  Black wire to Motor Terminal A1
  20. Solenoids R and F
    Solenoid R
    R1 – Copper Strap ti Solenoid Terminal R5, Black wire to Motor Terminal S1
    R2 – Green wire  to Speed Switch Terminal 11
    R3 – Black wire  to Solenoid Terminal F3
    R4 – Copper Strap to Solenoid Terminal F1
    R5 – Copper Strap to Solenoid Terminal R1
    R6 – Copper Strap to Solenoid Terminal F5, Black wire to Motor Termina A2
    Solenoid F
    F1 – Copper Strap to Solenoid Terminal R4, Black wire to Solenoid Terminal B2
    F2 – Blue wire to Speed Switch Terminal 12
    F3 – Black wire  to  Solenoid Terminal R3, Black wire to Solenoid Terminal B2
    F4 – Copper  Strap to Solenoid Terminal F6, Black wire to Motor Terminal S2
    F5 – Copper Strap to Solenoid Terminal R6
    F6 – Copper Strap to Solenoid Terminal F4
  21. Left Motor Diode
  22. Right Motor Diode
  23. Motor – 4 wires
    A1 – Black wire to Solenoid Terminal C4
    A2 – Black wire to Solenoid Terminal R6
    S1 – Black Wire to Solenoid Terminal R1
    S2 – Black Wire to Solenoid Terminal F4
  24. Batteries – Six 6-volt in series 36-volt, and two sets of 3 in series 18-volt
  25. Connector
  26. Resistor – Black wire to Solenoid Terminal C1, Black wire to Solenoid Terminal C4
  27. Circuit Breaker
  28. Delay Tube – Pin 2 White wire to Solenoid Terminal A3, Pin 5 Orange wire to  Speed Switch Terminal 9, Pin 8 Red  wire  to Solenoid Terminal A2
  29. Headlight
  30.  Headlight Switch
  31. Horn
  32. Horn Button
  33.  Ground Bolt – White wire to Headlight
  34. Tail Light – Green wire to Connector 25, Red wire to Connector 25 
  35. Brake Stop Switch – Red wire to Connector 25, Red wire to Connector 25 (2)

Troubleshooting Chart for the 1969-1970 Model DEC

SymptomPossible CauseRemedy
Batteries will not chargeAccelerator pedal not at rest position and wiper arm is not completely on the first contact blockRefer to Speed Switch Adjustment Section here
Corroded or loose battery connectionsCheck, clean and tighten connections
Faulty BatteryTest each Battery while completely disconnected from the series
Faulty ChargerUse multimeter and test output voltage
Will not go in forward or reverseFaulty batteries or connectionsInspect batteries and clean connections
Faulty key switchTest key switch with continuity tester
Faulty speed switchCheck speed switch connections
Solenoid "B" not energizingCheck cabling to Solenoid "B"
Test solenoid with procedure listed here
Faulty MotorFollow Motor trouble shooting procedures
Forward Works, no reverseFaulty key switchTest key switch with continuity tester
Solenoid "R" not energizingCheck cabling to Solenoid "R"
Test solenoid with procedure listed here
Solenoid "F" open between Large bottom terminalsCheck connections to Solenoid "B" large terminals.
Test solenoid with procedure listed here
Reverse works OK, no ForwardFaulty key switchTest key switch with continuity tester
Solenoid "R" open circuit on large bottom terminalsCheck connections to Solenoid "R" large terminals.
Test solenoid with procedure listed here
Solenoid "F" not EnergizingCheck connections to Solenoid "F" control terminals.
Test solenoid with procedure listed here
Speed 1 Works, no 2, 3, or 4Speed Switch wiper arm not making contact with 4th speed contact pad.Remove and inspect Speed Switch.
Speed Switch diode openCheck diode leads.
Speed 1 and 2 Works, no 3, or 4Micro switch not making the connection between NC and COMTest Micro Switch
Solenoid "A" not energizing, stuck openCheck connections to Solenoid "A" terminals.
Test solenoid with procedure listed here
Speed 3 and 4 Works, no 1 or 2Both Motor diodes openCheck diode condition
Solenoid "A" stuck closedCheck connections to Solenoid "A" control terminals.
Test solenoid with procedure listed here
Speed 3 and 4 works, no 1, or 2Short in Speed Switch DiodeInspect, repair, or replace.
Speed 2 and 4 works, no 1 or 3Solenoid "C" stuck closed bypassing ResistorTest solenoid "C" with procedure listed here
Open ResistorCheck Resistor connections.
Speed 1 and 3 works, no 2 or 4Solenoid "C" not energizing or stuck open passing all current through ResistorTest solenoid "C" with procedure listed here
Speed 1 and 4 works, no 2 or 3Time Delay Tube shortedCheck Time Delay Tube connections.
Speed 1, 2, and 3 works, no 4Time Delay Tube open or faultyCheck Time Delay Tube connections.
Speed 3 has a long delay or too short of a delayTime Delay Tube open faultyTest Time Delay Tube.
Front set of batteries goes dead or
Rear set of batteries goes dead
One Motor Diode is openCheck connections to Motor Diode or replace.

Conclusion

The battery configuration changed with the 1969 DEC putting the 6 batteries in the front and turned lengthwise. After 1970 the models  DE, DE-3 and DE-4 continue with the Three and Four Wheel model carts.

Recent Content