Test sequence

WARNING: This page is about a different variant/trim than selected.

Disconnect glow plug connector from glow plug.
Connect voltage tester using auxiliary clips from auxiliary cable set to battery positive (B+).

Fig 1: Connecting Voltage Tester Using Auxiliary Clips From Auxiliary Cable Set To Battery Positive

Place voltage tester probe on each glow plug one after another.
Diode lights up: glow plug OK

Diode does not light up: replace glow plug.
Remove and install glow plugs with Hinged socket 3220.
Tightening torque: 15 Nm (11 ft lb).