EPC Light Came on tonight ... loss of power. VCDS = 6557 - Sensor Reference Voltage B P0653 00 [172] - Voltage too High

[pancakeroll]

We fitted a dash cam yesterday with a battery monitoring box. Car was fine and we had it running off and on while fitting.

 

Next day - got to the bottom of the street, stutters and off it goes with EPC light showing.

 

Standing voltage of the battery was 11.8V

 

VCDS is showing the following...

 

1 Fault Found:6557 - Sensor Reference Voltage B

P0653 00 [036] - Voltage too High

Intermittent - Not Confirmed - Tested Since Memory Clear

Freeze Frame:

Fault Status: 00000001

Fault Priority: 2

Fault Frequency: 1

Mileage: 90738 km

Date: 2020.08.24

Time: 20:30:31

Engine speed: 1228.00 /min

Normed load value: 8.6 %

Vehicle speed: 0 km/h

Coolant temperature: 30 °C

Intake air temperature: 24 °C

Ambient air pressure: 1010 mbar

Voltage terminal 30: 14.116 V

Unlearning counter according OBD: 40

Engine speed: actual: 1216 /min

Readiness: 0110 0101

 

I tried jump starting (from another car) I notice that it's switching off (EPC illuminates) when the choke goes in. Therefore I'm thinking the battery is weak and I'm running on the alternator, when the choke goes the base level of the battery is consumed completely and is not receiving a charge strong enough, and this is throwing up the EPC error. Strangely (and don't knock me if I'm wrong here) it still cut out while the other car was connected, I would have assumed it shouldn't have done that as the other car was providing charging or is it that there is just not enough risidual charge in the battery to keep the engine going? I'm also wondering if this is a sign of a HT lead fault as other describe with EPC light?

 

I'm considering tomorrow (in daylight) removing the battery and sticking it on a trickle charger to see where we go from a fully charged battery. I'm on street parking. So will I have issues locking / unlocking the car after battery is remove. I'm planning on locking all doors using central console button (MFD to manual unlock). Remove battery lock with drivers door and when return unlock with drivers door.

 

Also with the battery removed do I have the potental of the alarm going off. I've ran an Audi before and I'm aware there is back up battery on the alarm sounder. It looks from research tonight - The Yeti is the same. As I'm several streets away I wouldn't want the alarm sounding as I will have no way of knowing.

 

Thanks in advance.

 

 

[Austin 7]

Hi

 

The Yeti doesn't have a choke as such, but the engine management may temporarily set a faster idling speed when cold, I assume that's what you are referring to. The alternator should charge the battery even at normal idling speed, and you should measure about 14.0 to 14.5 volts with the engine running.

 

It could be that your battery was already on its way out, and the extra current drain of the dashcam (there will be some even when the car isn't running) is taking its voltage too low.  You shouldn't see much less than 12.5 Volts on a good battery when it has been sat for a while with the engine off.  The problem with tired batteries is that the voltages once charged may seem OK, but their energy capacity in Ampere Hours drops to a much lower figure and they have no stamina.  If you imagine a tiny motorbike battery fitted inside a large case you will get the idea. If your car is a good starter and it's summer, you can get away with abattery in this condition for a while, but you are on borrowed time.

[pancakeroll]

On 25/08/2020 at 13:10, Austin 7 said:

Hi

 

The Yeti doesn't have a choke as such, but the engine management may temporarily set a faster idling speed when cold, I assume that's what you are referring to. The alternator should charge the battery even at normal idling speed, and you should measure about 14.0 to 14.5 volts with the engine running.

 

It could be that your battery was already on its way out, and the extra current drain of the dashcam (there will be some even when the car isn't running) is taking its voltage too low.  You shouldn't see much less than 12.5 Volts on a good battery when it has been sat for a while with the engine off.  The problem with tired batteries is that the voltages once charged may seem OK, but their energy capacity in Ampere Hours drops to a much lower figure and they have no stamina.  If you imagine a tiny motorbike battery fitted inside a large case you will get the idea. If your car is a good starter and it's summer, you can get away with abattery in this condition for a while, but you are on borrowed time.

 

Thanks!

 

Turned out the original turbo actuator was electronically reading incorrectly and bringing everything down by 5 volts. A new turbo actuator fitted later and it's sorted.

 

I now have to sort out the chain which is starting to clatter and I would like to fit an uprated battery too for the winter. Preferably the largest Varta/Bosch that I can, as I don't have much trust in the Halfords one currently in there.