Sevcon Troubleshooting
Page 11
Electrical Troubleshooting
Test 5. CONTACTOR COIL FAULT
Disconnect the 12-pin logic card connector from the Sevcon power unit.
Turn the key switch ON and perform the following tests:
TEST 5.1:
Check the voltage on the positive coil terminal of the ISO solenoid
(violet wire).
If the voltage is within approximately 1-volt of the battery
voltage, then skip ahead to test #5.2.
If the voltage is not within approximately 1-volt of the
battery voltage, then check the diode in the positive wire
to the ISO solenoid.
Stop trouble shooting here and repair the problem. When
the repair is completed, completely retest the vehicle before
lowering the drive wheels to the ground.
TEST 5.2:
Check the voltage on the negative coil terminal of the contactor
coil.
If the voltage is not within 1-volt of battery voltage, then
the contactor is bad and must be replaced.
NOTE: An open contactor coil should be accompanied by a 4-flash
code from the logic LED.
If the voltage is within 1-volt, then one of the four
following faults may have occurred:
Broken Wire: Check the wire from pin #8 in the 12-
Stop, do not continue. Reaching this point
indicates a failure in the Sevcon power unit
or an error was made during testing. Confirm
all previous tests were performed correctly
before replacing the Sevcon power unit.
STOP
pin logic card connector to the contactor coil negative terminal for open circuits.
Welded Solenoid Contacts: Test the solenoid for welded contact tips. There are two methods
for checking the contacts:
1. Disconnect the batteries and test the continuity across the contacts. If there is
continuity then the contact tips are welded.
2. With the key switch OFF, check the voltage at the B+ terminal on the Sevcon control
(see illustration on following page). If the voltage at the B+ terminal is at full battery
voltage then the contact tips are welded.
NOTE: Welded tips should be accompanied by a 4-flash code from the logic LED.
Shorted Solenoid Coil: Disconnect the logic card connector and measure the resistance
across the solenoid coil. Depending on the solenoid or contactor you vehicle is equipped
with, the resistance should be 25 ohms or higher (nominal). A reading less than 25 ohms
may indicate a shorted coil.
The control logic may have failed.
Summary of Contents for RE-380-36
Page 12: ...TAYLOR DUNN...
Page 30: ...TAYLOR DUNN...
Page 50: ...TAYLOR DUNN...
Page 64: ...Maintenance Service and Repair Steering Page 14 Exploded View of Steering Gear...
Page 90: ...TAYLOR DUNN...
Page 128: ...TAYLOR DUNN...
Page 143: ...Sevcon Troubleshooting Page 3 Electrical Troubleshooting Identifying Your Controller...
Page 162: ...TAYLOR DUNN...
Page 185: ...Wire Diagrams...
Page 190: ...Illustrated Parts Parts Page 4 Steering Linkage...
Page 192: ...Illustrated Parts Parts Page 6 Steering Gear 4 1 6 8 7 5 9 10 2 3 14 17 12 11 13 15 16...
Page 194: ...Illustrated Parts Parts Page 8 Front Suspension...
Page 196: ...Illustrated Parts Parts Page 10 Transmission primary reduction...
Page 198: ...Illustrated Parts Parts Page 12 Transmission secondary reduction Rear Axle...
Page 200: ...Illustrated Parts Parts Page 14 Rear Brakes Front Brakes optional Brake Body...
Page 202: ...Illustrated Parts Parts Page 16 Rear Suspension...
Page 204: ...Illustrated Parts Parts Page 18 Motor...
Page 206: ...Illustrated Parts Parts Page 20 Deadman Seat Brake...
Page 214: ...Illustrated Parts Parts Page 28 Wheels and Tires Ref wheel hub 1 2 5 assembly 4 3 6 7 8 9 10...
Page 218: ...Illustrated Parts Parts Page 32 Speed Control Panel R 3 80 36 1 2 4 5 6 6 7 8 3 9 10 11 12 13...
Page 220: ...Illustrated Parts Parts Page 34 Miscellaneous Electrical Miscellaneous Frame...
Page 222: ...Illustrated Parts Parts Page 36 Seat Cushions and Lights 1 2 3 4 5 6 7 8 9...
Page 230: ...Illustrated Parts Parts Page 44 Batteries 36 Volt 48 Volt...
Page 232: ...Illustrated Parts Parts Page 46 Decals Front Cowl Tray Battery Compartment...
Page 234: ...Illustrated Parts Parts Page 48 Trailer Hitch...
Page 236: ...Illustrated Parts Parts Page 50 Strobe Light Other Front End Options...
Page 238: ...Illustrated Parts Parts Page 52 Cab Cowl With Windshield Options...
Page 240: ...Illustrated Parts Parts Page 54 Optional Cab Accessories...
Page 242: ...Illustrated Parts Parts Page 56 Cab Door Options...
Page 244: ...Illustrated Parts Parts Page 58 Optional Top Cover...
Page 246: ...Illustrated Parts Parts Page 60 Rear Seat Rear Gate and Rear Deck...
Page 248: ...Illustrated Parts Parts Page 62 9 Side Panels...
Page 250: ...Illustrated Parts Parts Page 64 Front Bumper and Splash Pan...
Page 252: ...TAYLOR DUNN...