Hi Brian!
I have seen that you have knowlage on Eberspächer D5LC, I have a strange fault during start attempt!
It was working last spring 2020 and was not used until I tried it last December (2020) no light up! (Decarb done about 50hrs)
It's a D5LC 12 V (25 1861 01) from 1998 with a 7 day timer/modulator (401 00 191) with (indoor) temp sensor, (no diagnostic).
When starting it turns slower than normal, after 20-40 secunds fuel pump start "ticking" and diesel flow visable in the 1,5 mm transparent tube (small air bubbles).
At this time only ~4 A on the charger Amp meter, 14,2 Volt. This indicate that
glow plug is not "ON"
At the exhaust there is a smell of unburnt fuel. and I turn off the heating "mode" before logging any fault, and it goes into "ventilation" mode (4 min), and the
RPM increases but not to full!
Perf soo far;
Glow plug has 0.6 Ohm measured from the Current regulator plug, bench tested with 13,2 V in and 12.08V out, without load.
All conectors free from corosion
Flame sensor 1016 Ohm at control unit, Safety thermal switch Ok
The two resistors on PCB 12 ohm and 1,5 ohm is checked Ok
Control unit, Current regulator, PCB checked for corosion Ok.
Do you have any experiance with this kind of fault? Could you give a hint what would be your next step?
With Best Reg
Peter