About a year ago I put on an external voltage regulator and everything was good till 2 weeks ago . After warm up volts would go up to 14.5 for a while and then cut out . It will keep this up about every 10 to 20 min between cycles , no ryme or reason . Put on a rebuilt alt. and same thing . Put on a new voltage reg. and same thing . Also , when in the charge mod the lights have a pulse , dim slightly then bright , in a defenite rythem . Batteries ar also new and are showing 12.7 with voltmeter , checked seperately. I'm stumped....

 

14.5v is okay for the top end of the charging cycle. 12.7v is great for batteries after charging. What is the worry?

 

When it goes above 14.5 the check engine light comes on , then it will just go down and the needle drops well below 14, plus the light pulse when it is charging high. It use to stay steady just above 14 .

 

Double check your ground wire connections. A loose connection can cause "over charging", but 14.5 is borgerline, but should not be a problem.

 

All the connections on the alternater , voltage regulator and batteries are clean and good , done at least twice . I'll have to check further down the line . I can see the bad connection/wire causing the up and down charge , it's the lights pulsing that has me really puzzled .

 

Well it turned out to be the newly installed rebuilt alternator . Put another one on and all is good , charges properly and no more lights pulsing .