hi all. im new to this forum. my name is Ben from munich germany. my mitsubishi colt battery died so i put a new batt. in it and did a volt test . 15.5. so i bought a new altenator and im getting the same reading. 15.5 v. appreciate any help on this? regards p.s. ABS, battery lights are on and on board comp. not working....

 

What year?
Do you know if your replacement alternator came with a replacement voltage regulator built in? If not that's probably your problem.

It's also possible you got a 2nd bad alternator but overcharging is a less common failure state...

 

[B]2005 with built in regulator. altenator is brand new from hella. unlikely its the altenator. any other clues what it could be ? regards Ben

 

It's still possible it's bad... I've personally seen new alternators bad out of the box so don't 100% rule that out yet but for the moment lets assume it's good...

Did you make sure the spot it grounds to is clean and the cable is good? Another possibility is something is wrong with the field wiring and you are blowing voltage regulators. Check the input voltage to the regulator.

Some alternators are controlled by the computer you can try unplugging the smaller wiring harness (not the big battery charge cable) and see what happens to your voltage... In all likelihood it will drop off to battery voltage.

Check for charging system or alternator fuses and make sure they are good.

 

i forgot to mention that my neighbour is an ex- electrician and that he allready did a check on all the above. his baffled and thought it might be a common problem with mitsu.
anyways, he will look into it further 2morrow. thanks for your help....

 

Make sure you confirm he checked all of those items...

What was the result of disconnecting the control/voltage wire from the alternator?

 

sorry. didnt get back to you. been busy. i end up taking the car to a work shop. the problem was the small fuse box near the battery ( corrosion ). nevertheless thanx for your help....