I recently gave a boost to a friend of mine his car is a cadillac dts and the car i gave the boost with is a 2.5 xtype i have a battery light that is on every day or two. i had the battery checked and altenator and it passed inspection,i also boosted my x type a while ago with a echo,maybe i should have my car started while connecting the battery to a larger engine and that may charge my altenator or battery....or fix the problem im having?.the mechanic said the altenator passed inspection ..but not with flying coulors.

 

From what Ive learnt from my past experiences NEVERRRRR EVERRRRRR EVEEEERRR give a boost to anyyyy car with a luxury cars. I myself have a old *** pontiac for given boosts.

 

Did your mechanic provide you with the voltage readings? Please post them up if so.

 

Well i gave someone a boost with my x-type a while ago, i had no such problems. Maybe change in battery is due? I am not sure myself, Try using a battery from a nother car. and see if you still have the same error?

 

i have had the same problem from my 2.5 due to my subs and running the air conditioning lately. i have noticed too that the battery is considerable weaker by the way it starts. it is getting close to being due for a battery. Jump starts are hard on a battery and charging system. never jump the other car with yours running because it will cause voltage spikes from the alternator charging at full amperage and dropping sharply.