2002 325ci starter issue?

[fxoaxaca]

My son's '02 325ci has been acting strangely lately. Symptoms are as follows:

• One HID light flickers intermittently at times
• Car will not start without warning even though OEM battery shows fully charged and receives proper consistent charging voltage from alternator
• When car has not started (twice recently) it starts when jumper cables are used.
• When car does not start, interior lights, radio and headlights do work. Attempting to start only generates a clicking sound from under the hood.
• Today, car started but transmission failure light came on and car went to what seemed like a "limp mode". Later, car started properly and transmission failure light went off and car was no longer in "limp mode".

After doing some research, I have narrowed things down to a bad starter or starter solenoid. I understand that to changes these out is a difficult DIY project. Any suggestions as to other possibilities? I did purchase a new battery just in case. Does anything in the above list of symptoms indicate that a new battery would help? Thanks!

[Big Evil]

Interior lights and radio don't really mean squat, they use very low amounts of power. Clicking while trying to start indicates low battery, generally not bad starter (that would be one loud clack with no engine movement).

New battery IS a good idea, also get the alternator checked. I'm not sure when the IBS made it's way onto the three's, but if equipped it could be getting dodgy (part of neg. battery cable).