Checking Glow Plugs — Model 530d (BMW 5 Series E39)

Removal

Prerequisite for checking: the battery voltage must be more than 9 volts. If necessary, charge the battery.

Caution: If the glow plugs are not working properly, be sure to check the fuses located behind the glove compartment.

Examination

Read the contents of the DDE system fault code memory. Check the received messages, eliminate the faults and erase the contents of the memory.

Turn off the ignition.

Remove the case fine air filters.



Remove bolts "1".

Remove cover "2" from the electronics unit.



Disconnect plug "1" from glow plug relay "2".

The location of the contacts on the wire harness plug:

• Glow Plug Pin Winding for Cylinder 1 = Socket 9 - Black / Green
• Glow Plug Pin Winding for Cylinder 2 = Socket 8 - Black / Purple
• Glow Plug Pin Winding for Cylinder 3 = Socket 7 - Black/Yellow.
• Glow Plug Pin Winding for Cylinder 4 = Socket 3 - Black/Red.
• Glow Plug Pin Winding for Cylinder 5 = Socket 2 - Black/White.
• Glow Plug Pin Winding for Cylinder 6 = Socket 1 - Black/Brown.

Warning: Do not switch on the glow plugs when they are removed. This will not provide sufficient heat dissipation from the glow plugs. There is a risk of injury and fire!

Connect an ammeter between the positive terminal of the battery and the socket of the wire harness plug, see the location of the contacts on the wire harness plug.

Turn on the ignition and measure the current.

Specified value: After the glow plug has been in operation for approximately 30 seconds at a battery voltage of 11±0.5 volts, the current through the glow plug should be 10 amperes.

If necessary, remove the glow plug after cooling and measure its resistance. Prescribed value: 0.5-2.0 Ω.

Attention: If a defect in the glow plug is detected during inspection, it is necessary to check:

• wire from relay to glow plug;
• glow plug connector;
• glow plug repair work;
• 100 amp fuse.