Glow Plug: Testing and Inspection

1. Disconnect glow plug and indicator lamp connectors from pre-heating control unit. Control unit is attached to side of fuse/relay panel. Glow plug connector is connector farthest from B+ connecting stud.
2. Connect ohmmeter between each glow plug terminal in connector and ground. Resistance for each plug should be .4 - .6 ohm at 68°F.
3. Connect ammeter between B+ source and each glow plug terminal in connector, noting meter reading for each glow plug after 5 seconds. Meter reading should be 13 - 15 amperes. Do not test glow plug current draw with glow plugs removed.
4. Replace glow plugs that do not perform as outlined.