FixVault

Relay Circuit Test

  1. The relay common feed terminal (87) is connected to battery voltage and should be hot at all times. If okay, go to next step. If not okay, repair open circuit to PDC fuse as required.
  2. The relay normally closed terminal (87A) is not used for this application. Go to next step.
  3. The relay normally open terminal (79) is connected to common feed terminal (87) in energized position. This terminal supplies battery voltage to starter solenoid field coils. There should be continuity between cavity for relay terminal No. 79 and starter solenoid terminal at all times. If okay, go to next step. If not okay, repair open circuit to starter solenoid as required.
  4. The coil battery terminal (81) is connected to electromagnet in relay. It is energized when ignition switch is held in Start position and Clutch Interlock Switch is closed (clutch depressed). Check for battery voltage at cavity for relay terminal No. 81 with ignition switch in Start position and clutch depressed, and no voltage when ignition switch is released to On position. If okay, go to next step. If not okay, check for an open or short circuit to ignition switch and repair, if required. If circuit to ignition switch is okay, check and repair ignition switch as necessary.
  5. The electromagnet coil ground terminal (83) is connected to ground. Check for continuity to ground at cavity for relay terminal No. 83. If not okay, check for an open or short circuit to ground and repair.