Checking the starting aid system
Check the glow duration of the glow plug indicator lamp. Turn the starter key to the ON position, measure the lamp duration.
Location: under the dashboard, on the passenger side. Disconnect the timer connector; check the circuits on the harness side according to the tables below.
Checking Relay No. 1 Glow Plugs
Location: in the engine compartment, at the rear.
1. Check relay circuits.
A) Using an ohmmeter, check for continuity between terminals E and G.
b) Check for continuity in the circuit between terminals B and G. If the circuits are not as specified, replace the relay.
2. Check relay operation.
A) Apply battery voltage to terminals E and G.
b) Using an ohmmeter, check for continuity between terminals B and G.
If relay operation is not as specified, replace the relay.
Checking the timer (type 1)
Check timer circuits.
Checking Relay No. 2 Glow Plugs
Location: under the dashboard, on the passenger side.
1. Check relay circuits.
A) Using an ohmmeter, check for continuity between terminals E and G.
b) Check for continuity between terminals B and G.
If the conditions are not met, replace the relay.
2. Check relay operation.
A) Apply battery voltage to terminals E and G.
b) Using an ohmmeter, check for continuity between terminals B and G.
If relay operation is not as specified, replace the relay.
Checking glow plugs
Using an ohmmeter, check for continuity between the glow plug terminal and ground. If there is no continuity, replace the glow plug.
Note: Care must be taken not to damage the glow plug guard, as this may cause an open circuit or shorten the life of the spark plug.
Do not allow oil or gasoline to come into contact with the positive terminal of the glow plug while cleaning it.
When inspecting the condition of the spark plug, be sure to remove any traces of oil from the spark plug terminal and Bakelite washer using a dry cloth.
Be careful not to apply more than 7 volts to the spark plug, as this voltage can cause the spark plug to burn out.
Checking the glow plug resistor
Check the condition of the glow plug resistor.
Using an ohmmeter, check for continuity between the resistor terminals. If there is no continuity, then replace the resistor.
Checking the coolant temperature sensor
Check the condition of the temperature sensor.
Using an ohmmeter, measure the resistance between the sensor terminals. If the resistance is out of specification, replace the sensor (see diagram).