- the engine is cold (ambient temperature),
- the battery is fully charged,
- battery voltage is not less than 11.5 volts.
Check the 80 amp strip fuse in the relay box.
Unscrew the glow plug wires.
Connect the voltage tester to the positive terminal of the battery and connect it in series to each glow plug.
If the LED lights up: the glow plug is OK.
If the LED does not light, the glow plug is defective and must be replaced.
- Tightening torque: 25±5 Nm;
- for 4 inch candle: 20±1 nm.
Caution: Do not exceed the specified tightening torques, as this will overtighten the annular gap between the spark plug rod and the threaded part and the spark plug will fail prematurely. If the rods have burnt out, follow the instructions below.
Screw on and lightly tighten the wire onto the spark plug with a tightening torque of 5 Nm.
Checking the glow plug relay
Remove the glow timer relay. The glow timer relay is located in the relay box on the right side of the rear of the engine compartment under the main relay and the fuel filter heater relay.
Connect the voltage tester to terminal 30 (+) and ground (-). The LED should light up, otherwise check the power supply from the battery.
Connect a voltage tester to terminal 15 and ground. The LED should light up, otherwise check the voltage supply from the ignition switch.
If the tester LED lights, check the glow plug wires for breakage and replace if necessary. Otherwise, replace the glow plug timer relay.
This article is based on information from the website «BMWman.ru»