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When I turn the ignition on I get no check engine light on the dash.. the car was running I left lights on got a flat battery.. I charged battery up, chucked it back in. now when I turn on the key on the check engine light doesn’t show up.. I can’t hear the fuel pump prime up either. All fuses are fine and I’ve swapped out the ecu for a known working one.. where should I start to look now?
I'm not really the person to answer electric problems but have you confirmed that the actual light in the dashboard is functional and if it is have you bridged the diagnosis terminals to get a code if there is one. Other people with greater familiarity with the electronic of the earlier ones should be able to offer more insight.
Temeraire (2018 quasar grey automatic)
One of the last 200ish of the gen3s, probably.
ADOS Attention Deficit Ooooh Shiny!
I think the question I have is what is your concern - that the check engine light isn't coming on - or - is it perhaps that the engine isn't starting?
The fact that you mention not hearing the fuel pump prime suggests that the engine isn't starting, and if that is the case, then I'm sure that would be an important detail.
Swapping the ECU wouldn't have been my first step, but I suppose if one was available it doesn't hurt, not hearing the fuel pump prime suggests that it's not getting power, which is also one of the things that the check engine light not coming on might point to, and the fact that the problem essentially started with a flat battery might also point to that direction.
Do you have a volt meter and are you familiar with it's use?
If the engine isn't starting, and the check engine light doesn't come on when the ignition is on, my next question would be what are the other dash lights that come on when you turn the ignition on?
Are you at least getting the charge and oil pressure lights?
Does the engine crank when you turn the key to start?
So the car used to run until flat battery.. it cranks over but doesn’t fire. Have checked all fuses and swapped ecu with a known good one.. I haven’t checked if the bulb is blown or not.. I’m guessing it should still start if bulb was but fuel pump not priming and I’m guessing it’s got to do with cel…. All the other dash lights come on during ignition
