Wait Lamp Pulses Slowly on & Off

Fig. 2 Glow plug wiring schematic (Part 1 of 2). 1982-83 models:

Fig. 2 Glow plug wiring schematic (Part 2 of 2). 1982-83 models:

1. With "Wait" lamp pulsing, connect suitable test lamp between white and yellow wires of wait lamp control relay, Fig. 2.
2. If test light is on when "Wait" lamp is off, and off when "Wait" lamp is on, replace "Wait" lamp control relay.
3. If test light does not turn on, connect test lamp between ground and orange or orange/black wires at thermal controller. With "Wait" lamp pulsing, confirm test light pulses on and off with "Wait" lamp.
4. If test lamp does not light, connect test lamp to front red wire and rear dark blue/black wire terminals of glow plug relay. Defect may be in red wire between battery and glow plug relay, or in black, dark blue, dark green, and orange or orange/black wires between relay and thermal controller or glow plug relay. Repair as necessary.
5. If test light flashes on and off with "Wait" lamp when connected to orange or orange/black wires at thermal controller, then connect test light between black wire at controller and ground.
6. If test lamp flashes on and off, repair black wire between controller and ground.
7. If test lamp does not light, replace controller.