lights causing major drop in volts

[chefplw]

have been chasing electrical problems mget one fixed or so I think and a new(?) one surfaces. I am enjoying the fact that I m learning. I guess thats why we own them and not some newer d90.
so here goes. the other nite I drove around and it started to get dark. for the first time i need the lights for more than just checking to see if they all worked. as i was rideing around a realized that they were growing dimmer. I looked at the volt meter and it was showing about 10 as I continue on it keep dropping. I thought maybe the battery wasnt holding a charge.
I charge it fully. and started to check somethings 1) checked to see if drain without running nope 2) started up runnig shows 12v at idle almost 14v at 2000 rpm. so seem to be charging 3) turn on all lights low beam, running lights and set of 60watt driving lights and volts drop to 10v on gauge.
so now my questions :confused: 1) head lites are aftermarket halogens (H4 i think) without any relays so very weak is lack of relay possible problem 2) my other guess was that maybe 8 year old optima battery is some how problem. 3) PO as wires rurnning all over place so thinking of gettingt new harness and starting fresh.sorry for being so long winded but tried to give all info. just trying to get it running somewhat reliable for summer on cape cod. thanks for the help that is sure to come:D

[alaskajosh]

Sounds more like a charging/alternator issue than anything to do with the lights, per se. The lights are just visibly manifesting the lack of charge.

You might check the "charge" lamp (the bulb itself) behind your instrument cluster. Stupidly, if that bulb fails your charging days are over.

Let us know how it goes-
Kind regards, Josh

[I Leak Oil]

Get your battery load tested.
Jason T.

[thixon]

which alternator do you have? You also mention wiring all over the place. Is this a stock harness thats been hacked up, or something else?

Without more info, I'd say either the alt is bad, or does'nt have enough punch to keep up with all the accessories you have.

Need more info.

[109 Pretender]

I noticed everyone mentioning ck'ing your "alternator" - but I didn't see you mention whether you had an alt. or generator. The halogen lights will draw too much current @ idle for a gen. and yes, the lights will dim some. The 8 year old batt. is getting long in the tooth - but, if it'll start the engine w/o problems.... still worth a load test though. Have the gen/alt. ck'd for output. Alternators will generally output enough @ idle to not cause any problems w/dimming lights - if it's up to snuff. All the extra wiring needs to be sorted soon - otherwise the ugly Prince of darkness - Lord Lucas himself - may strike yet another circuit and cause endless, ongoing problems. Good news is Rovers have very simple electrical systems and can be fixed w/new harnesses from our sponsor RN.

Good Luck!

[chefplw]

got things fixed for now. replace the battery 8 years old it eas borderline on the load test. also found some original worn out on the ground side of the headlights. for some reason po used some new wiring some orig wire with butt connectors. replaced and soder. I plan on replacing the wiring with aftermarket harness as soon as I can afford it. next on list is some new springs first 43 year old ones are starting to look like they may fail soon. the PO did suggest replacing them. hope my tax refund comes fast.
thanks for the help Phil:thumb-up: