Battery not charging after standing for 1 week with hard frost mornings

[EZ-now]

My roadster has sat stationary outside for a week or so while I have driven the family car during my wife's no driving period following the C-Section birth of our second daughter (fortunately in better health than my roadster that I cannot believe I still own when we are a family of 4 now!)

The mornings have been very chilly with an icy windscreen for a couple of days.

I tried to start the car but couldn't. I topped up the battery and jumped it from the family car, giving it a charge for 20 minutes or so. After letting it run on it's own it ticked over for a few minutes and then died again. I assumed that the battery had had it's day and bought a new one.

I took it out for a spin locally to evaluate. After a few miles the battery light came on.

I have had the SAM out and dried it for a couple of days in case it is condensation because of the cold mornings. The SAM re-installed OK but the problem persisted.

I finally checked the battery voltage and have 11.5V not running and running so there is no charge getting to the battery.

I'm wondering what components there may be other than the alternator that may require checking as I cannot imagine how the alternator has failed just from standing with no symptoms before the idle period.

Any help gratefully appreciated :-)

[mac999]

The alternator is known to seize up so that should be your next item to check,make sure its spinning freely

[EZ-now]

Hi mac999,

There hasn't been any screaming while I've run it around and idled it on the drive and I think that the belt hasn't been slipping prior to this idle period as it has been electrically sweet since I bought it a couple of years ago.

I can't see the alternator from above the engine can I?

[tolsen]

How about looking under?

[tolsen]

How about looking under car if you can't see belt from above?

[EZ-now]

I've been underneath the engine bay and found the alternator. I sprayed some PTFE maintenance spray into the housing. I've turned the spindle about a single turn, moving it back and forth after each flat on the nut. It spins when the engine is running but there is still no charge.

[tolsen]

Check earth leads in engine bay. By checking I mean undoing, cleaning and refitting with some protective grease. Then do same with connectors at back side of alternator. If still no charge, it is possible your alternator has given up the ghost.

[EZ-now]

Thank you tolsen. The engine bay is very visually obscured. Can anybody please describe how many earths I should look for and where abouts they are?

[EZ-now]

I've found the main engine earth described on Evilution. Any others that I should look for?

[tolsen]

There are 3 earths in engine bay:

1. Top forward left corner just below level of hatch. A bunch of brown wires are clamped to chassis.
2. Main earth strap from bell housing to chassis aft of hatch. This strap is uninsulated and is clipped to TIK pipe. It is known to disintegrate into dust due to corrosion.
3. Of lesser importance is earth strap from transmission to subframe. This is missing on my 450 Cdi but I have seen it on petrol 450 Smarts.

Positions may be slightly different on Roadsters.

[EZ-now]

Brilliant. Thanks. I'll be back from shopping to look at them shortly :-)

[tolsen]

Remember my advice in post 7. Check them properly, not just look an count.

I had a no charge problem with my Renault Kangoo. Changed alternator 3 times and no improvement. Each alternator bench tested fine. It turned out in the end the cause was bad earth on main earth strap at connection to chassis. Quite an embarrassing saga and yet so easy to check. Just connect a good jump lead from engine to battery minus pole and see if there are improvements.

[EZ-now]

Sorry for appearing to write and run. I'm very appreciative of the help but got rained off doing the earths yesterday and am now back at work, plus a newborn, and our mortgage completes on Friday and and and etc. After seeing the green tarnished state of the main earth I'm satisfied that it would appreciate a new set as per the evilution roadster Earth upgrade. I've had a significantly diminished fuel economy over the two years. I nearly hit 400 miles a tank when I bought the car and now struggle to get 370ish. So please don't think me rude suddenly disappearing. I just have other things on and a wife who can't drive due to her c section so I also have use of the family car. It's breaking my heart to see it backed up on ramps on the drive at the moment though :-(

[EZ-now]

Hi Guys, I finally found time besides new child, Christmas and buying a new house (thankfully with a garage) to get under the car... The alternator spins fine. I could not get at the 'bunch of wires' earth at the top left of the engine bay and could not reach the bell housing end of the main earth. I have stripped, cleaned and copper greased the chassis end of that one though. Also the two in the front boot. I could not find a third in the engine bay. I cannot get at the back of the alternator. I have tried connecting the battery negative directly to the engine and still have the same result. Am I looking at a new alternator? :-( Thanks for the help and sorry again for the long delay.

[Evilution]

Yep, new alternator. They do "just die", the one in my Roadster was fine one day and borked the next.
Buy a replacement from smart, don't get a pattern copy or get your reconditioned. I have never had luck with either.