Glow Plug System: Testing and Inspection

Testing preglow system






A1e16 Preglow indicator lamp
B11/8 Coolant temperature sensor, afterglow
N14 Preglow time relay
R9 Glow plugs

Perform test in accordance with test program "preglow system".

Commercially available tester






Note: Circuit protection of preglow circuit.
An electronic short circuit protection is installed in the preglow time relay. In the event of a short circuit in the glow plugs or in the wiring, the circuit is interrupted.
The preglow time relay is operational again once the short circuit has been rectified and the ignition key turned back to position "0".

Designation of the two preglow time relay couplings






Couplings with the pins T, 31, 50, 15, LA: (1.1) to (1.5).
Coupling with the pins G1 - G6: (2.1) to (2.6)

Wiring diagrams of preglow system, refer to Computers and Control Systems - Diagrams - Electrical Electrical Diagrams

Test program preglow system










Current clamp over glow plug lead

N14 Preglow time relay
N14x1 Coupling at preglow time relay