Adrock wrote:If the glow plugs are 6 volt I would assume 2 are wired in series, (or does the controller divide the voltage and run them all parallel?) If wired in series, and one is shorting it will not drop 6 volts across each but rather 12 across the one remaining with resistance. Meaning it will heat up 4 times faster, and if your temp sensor is in that neighbourhood, it will function correctly. Again I am assuming the temp sensor measures temperature from one location rather than at all the glow plugs, and may be wrong.
the glow plugs are wired in parallel and get 12v for the initial hit then 6v though the step down module that is right next to the glow plug relay. I posted a get repost with diagrams a couple times but atm I'm not gong to take the time to find it and post it again :) there are also I couple of different systems I believe so this can complicate the internet diagnosis.
