The quick-start glowplugs are designed for a voltage of between 5.3 and 7.8 Volts. Â€¢ Bit serial data interface (BSD) and electrical leadsĪ heater plug relay as in the case of DDE 4.0 is not fitted. The glowplug system consists of the following components: Fault code 3505 'Preheating system' is stored in both cases. The DDE control unit receives a fault signal from the preheater relay in the form of the S_GRS signal if there is a fault in the preheater plugs, preheater relay or in the voltage supply of the relay (type of fault 'preheater system fault'). The DDE control unit itself detects a short/break in relay activation (type of fault 'activation short-circuit. 10 seconds if after the preheating time has elapsed the engine is not started and the ignition remain on. The preheating time increases as the temperature decreases.Īfter-heating takes place after engine start at temperatures below 20 Â☌ in order to improve idle and exhaust characteristics. The preheating duration is dependent on the engine coolant temperature and battery voltage and is indicated by the preheating/DDE indicator.Īt temperatures below 5 Â☌, preheating takes place for at least 4 seconds.

The heater plugs are designed as sheathed-element glow plugs. The relay is switched by the DDE control unit. The voltage for the preheater plugs is supplied via the preheater relay.

I got curious so I googled a bit and found some conflicting info: Regarding glow plugs, I personally doubt they would only turn on at the temperature. So on cold temps turning over is aning the starter spins the engine slower during cold temps? Is it slower from the moment you turn the key or does it start spinning normally initially and then begin to spin slower and slower? Nice W115! Mods, sorry, don't ban us please lol!

Bit serial data interface signal bmw