After trying to diagnoise the starting problems with my 2005 focus climate and reading replies from members i have seen a lot of talk about calcium batteries and how "apprently" people who have used to lead batteries 'not all people' have experienced some unusual electrical faults similar to mine...

does anyone have clarification on this?

curious to know about this smart charging etc...and the effectivness compared to regular lead batteries couldnt tell u the difference betwen the two to be honest!

when it comes to stripping an engine down and bodywork ill happily do it all but electrics realy are not my thing...too fiddly ;) and the rhyme the blue one connects the red one and so forth doesnt apply to cars :D

thanks guys look forward to hearing your responses

any ford with smart charge requires a lead calcium or silver battery, this is due to the higher charging voltages than normal when cold - the system takes advantage of a cold battery taking a higher charge rate.

using a standard lead acid will probably boil the electrolyte inside it and destroy it in no time.

so basically any modern ford should have one..

Ditto, what he said ^^^^^^^^^^. I have a silver calcium . All I know is a lead batt with smart charge system is a mega NO NO unless u want fry the batt and the charge system.....

got it :D i have just bought this vehicle and im under the impression that it has a lead acid battery i will check first thing in morning but a few places and sources have told me that it could be the cause of all issues :) nobody can quitge explain why but there some strange electrical faults that seem to arise because of this simple oversite?

Its very simple -

A modern car uses complicated digital systems, it has literally millions of components

the digital systems are fed by analog sensors - these analog sensors measure voltage or resistance

for example - a temprature sensor - the resistance or voltage changes depending on (head) temprature

this analog voltage or resistance is converted into digital (via an A-D (analog-digital) converter) then this data is read by the ECU (engine control unit)

The system is designed for a silver- calcium battery, (which operates at a higher voltage)

If a regular lead - acid battery is used, this can change the overall voltage, this can make the sensors give "false" information which can generate error codes and running problems (because the ECU is being fed incorrect information )

this is why the wrong battery can cause so many problems - it affects many sensors on the car (and many error codes may be generated)

What he said.

Very simple a cold battery takes a better charge so the smart charge system detects a cold battery and puts 14.4 v into the battery a normal leadvacid will start to boil at this voltage a silver or calcium battery uses silvet or calcium plates on the terminals which can cooe with a higher voltage as the electrolyte in the battery heats up from the charging the smart charge lowers the voltage to the battery so from 14.4 on a cold battery it can drop to say 13.9 on a hot charged battery prolonging the battery life a lead acid will still be boiling and over charging sending false signals to various sensors causing electrical issues such as erratic dials battery charging lights going on and off stereo interference in worse cases it ruins the smart charge over loads the alternator ford alts are quite good but most garages know nowt about smart charge fit the wrong batteries and cause issues

Can having the wrong battery cause the lights to pulse bringht and dim both inside and outside the car ?

yep.

The smart charge system operates based on constantly reading the batteries input and output, as well as the alternators inpput and output. Only Silver calcium can take up to 18v, if that happened to a lead acid, it would throw it into chaos;

Thankyou for your help I have it booked in to be tested in the morning so hopefully I will have some answers then