EPC Light

[Nickg912]

Hi all

 

i Parked up and let the engine stop on its own wit the stop/start system for around 15 minutes and when i went to start the car back up again it came up with the EPC light on the dash and the check engine light and the car would not start but all the electric equipment was working, lights/infrotainment system. after a few minutes of letting the car just sit there with nothing on the car started back up again and i was able to drive again without the light showing up 

 

any suggestions on what could have caused this 

[nta16]

Probably the computers taking over and getting their panties in a twist, if you were running electrical stuff while parked up, on the phone, listening to music, or even if not I always go for possibly your car battery is low, even if electric stuff was working and rhe car starts up.

 

Other side is the throttle sensor, you might have done something to upset it or not done some thing you should have to keep it happy or gawd knows how many other electrical/electronic/programming deviations might be involved.

 

Perhaps you didn't turn the ignition off or done something else.

 

How many miles on it, what's the service history, how's it been looked after.

 

That me out of ideas, you could do a scan and see if any error codes were logged, check the battery and if required give it a long slow low recharge out of or disconnected from the car overnight and longer if possible, that might slay two flying creatures with one pebble.

 

[rum4mo]

Without try to replicate this, 15 minutes seems quite a long time for the auto stop/start to leave the engine off, I would have thought that the cabin temperature demand or the battery voltage state would have switched it back on before 15 minutes, mind you, if I considered that the traffic was not moving for 15 minutes, I would have switched the engine off probably within 5 minutes.

[nta16]

I was taking it as just parking up, pulled over ,or stopped for a while -possibly to listen to The News and The Archers.

 

[TerFar]

Most likely problem will be a not too well charged battery. I disconnected the BCM (battery control module) sensor from the battery negative terminal to permanently override the Start/Stop malarkey and to ensure that the battery gets fully charged and not stuck on 80% by the BCM. IMO, the BCM is just a crazy EU influenced piece of programming garbage to eek out an extra 0.00000000001% fuel improvement. All it does is stop the battery fully charging. I'm not dead against Start/Stop, but as I rarely do any driving in heavy start/stop traffic, it is is something that I don't miss. As you have probably noticed, when the battery gets low, the BCM inhibits the start/stop function until the battery level improves anyway.

[nta16]

There's so much programming garbage on modern cars to get the nth degree of mpg and (pretend sometimes) much lower emissions as internal combustion engines are such ancient dirty technology but obvious the car manufacturer's don't want to admit to any of this (bear in mind I drive a car from 1973 so worse, but more honest).

 

For the thread problem-

as always, I'm for battery too, I go for charging the battery off the car at least overnight on a long low slow recharge.

 

I wonder what Nickg912 will find.

 

Edited 15 November, 2021 by nta16
spelling

[JGrindel]

21 hours ago, TerFar said:

Most likely problem will be a not too well charged battery. I disconnected the BCM (battery control module) sensor from the battery negative terminal to permanently override the Start/Stop malarkey and to ensure that the battery gets fully charged and not stuck on 80% by the BCM. IMO, the BCM is just a crazy EU influenced piece of programming garbage to eek out an extra 0.00000000001% fuel improvement. All it does is stop the battery fully charging. I'm not dead against Start/Stop, but as I rarely do any driving in heavy start/stop traffic, it is is something that I don't miss. As you have probably noticed, when the battery gets low, the BCM inhibits the start/stop function until the battery level improves anyway.

Quite common for people to do that. Turning the SS off via the button on long journeys allows the car to charge the battery over 80% too. 

[TerFar]

That is correct, but we have been very much limited to local journeys for the last couple of years, which is why we fully disabled the function. If only they had made the S/S override switch 'sticky' rather than resetting itself when you switch off the ignition.

It's another small instance of loss of freedom of choice where we are dictated to instead of given a democratic option.

[JGrindel]

13 minutes ago, TerFar said:

That is correct, but we have been very much limited to local journeys for the last couple of years, which is why we fully disabled the function. If only they had made the S/S override switch 'sticky' rather than resetting itself when you switch off the ignition.

It's another small instance of loss of freedom of choice where we are dictated to instead of given a democratic option.

If you have coding tools you can code it out but it will throw an error etc. Chichester is aweful for battery charging anyway... slow bypass and traffic...

[Breezy_Pete]

20 minutes ago, TerFar said:

If only they had made the S/S override switch 'sticky'

You can buy little inline electronic modules that remember the last chosen mode for the next journey.   Not too expensive as it's quite an easy thing to do electronically.

Doubt this one is model-suitable, but this sort of thing: Automatic Stop Start Engine System Off Device Control Sensor Plug Stop Cancel | eBay

[nta16]

Or just push the button every time needed, I know it's a pain but you can get into the habit, to paraphrase Danny, why trust one program and not the other.

 

[TerFar]

The options are not as simple as disconnecting the sensor connection from the negative battery terminal: easy, removes the need to remember to press the override button, takes 2 minutes and is just as easily reversible at any time. 😉