Being a Auto Electrician charging has always been a issue I've always been asked to check and attend to, for that very reason I like to know whats going on in my own cars, so I run a plug into the cigar socket one of those Voltmeters you get off ebay. Having checked it against my Fluke Workshop Meter and satisfied it was within a acceptable tolerance popped one into my 2015 1.4 TFSI.
Driving around I was seeing voltages as low as 11.9v and then 14.3v and then the ecu shut down to alternator again to drive along until a load once again comes onto the system and it all kicks back into life i.e lights on heater blower and more. Last week I was driving along with the wipers on slow and the battery voltage was 11.7v and the wiper were creeping across the screen like a old vacuum system off a 1957 Ford Squire van, lights on boom 14.1v wipers back to normal.
I always switch Stop/Start off as thats another hate of mine, beating the ring gear and starter to death.
Time to see what could be done to stop smart charging (which kills batteries before their time).
On the negative terminal of the battery is a small Black Sensor built into the lead, this has a plug with 2 wire going off to the ecu to monitor the voltage and thus switch the alternator on/off. I disconnected the 2 wire connector from the Sensor and instantly the voltage is now controlled by the internal Alternators regulator. Voltage now is 14v constant no more letting the battery provide the power, powered like a charging system used to be. No warning lights, no fault codes.
Ford have a software fix for people to turn off smart charging as some are experiencing flat batteries over short trips, as far as I'm aware VAG do not offer this.
Obviously without a voltmeter plugged into the cigar socket 99% of owners are unaware of anything going on charging wise, but their are a large number of people on VAG Forums on all makes with charging issues down to Smart Charging.
Been a month now and no issues and I don't expect any, am I worried about the extra small amount of energy taken to run the Alternator and the manufactures claims of improved economy ? Absolutely Not.
Obviously information only and you make up your own mind on whats right for your circumstances and style of driving.
Driving around I was seeing voltages as low as 11.9v and then 14.3v and then the ecu shut down to alternator again to drive along until a load once again comes onto the system and it all kicks back into life i.e lights on heater blower and more. Last week I was driving along with the wipers on slow and the battery voltage was 11.7v and the wiper were creeping across the screen like a old vacuum system off a 1957 Ford Squire van, lights on boom 14.1v wipers back to normal.
I always switch Stop/Start off as thats another hate of mine, beating the ring gear and starter to death.
Time to see what could be done to stop smart charging (which kills batteries before their time).
On the negative terminal of the battery is a small Black Sensor built into the lead, this has a plug with 2 wire going off to the ecu to monitor the voltage and thus switch the alternator on/off. I disconnected the 2 wire connector from the Sensor and instantly the voltage is now controlled by the internal Alternators regulator. Voltage now is 14v constant no more letting the battery provide the power, powered like a charging system used to be. No warning lights, no fault codes.
Ford have a software fix for people to turn off smart charging as some are experiencing flat batteries over short trips, as far as I'm aware VAG do not offer this.
Obviously without a voltmeter plugged into the cigar socket 99% of owners are unaware of anything going on charging wise, but their are a large number of people on VAG Forums on all makes with charging issues down to Smart Charging.
Been a month now and no issues and I don't expect any, am I worried about the extra small amount of energy taken to run the Alternator and the manufactures claims of improved economy ? Absolutely Not.
Obviously information only and you make up your own mind on whats right for your circumstances and style of driving.
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