Author Topic: SL Revalations  (Read 16590 times)

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #30 on: October 23, 2014, 06:30:23 PM »
The SL is fitted with two batteries.
The front battery is solely used for starting.  The rear battery looks after everything else.  This means that you can start the car with "the other battery" down to about 10.5 volts.
The down side is that with only one alternator there has to be a split charging system.  This is looked after by a (very expensive) battery charging module. This does not like seeing a high reverse voltage.  This means that you can only, safely charge the front battery.  If you you want to put a charger on the rear battery you must disconnect it from the car.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

tenpin

  • Administrator
  • Hero Member
  • *****
  • Posts: 2033
  • Karma: +4/-0
    • View Profile
Re: SL Revalations
« Reply #31 on: October 24, 2014, 03:54:05 PM »
According to the manual:
"Always disconnect the battery for electrical consumers in the boot first - even if you only wish to charge the starter battery. Otherwise the vehicle's electronics system may be damaged."


 - tenpin

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #32 on: October 24, 2014, 04:57:28 PM »
That's what I said.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #33 on: October 25, 2014, 09:52:13 AM »
Tenpin tells me that it's best to disconnect the rear battery before disconnecting the front battery.  Not a bad idea.  The number one rule is " Don't mess with Merc electrics"

What is vital is that whichever battery you disconnect you must disconnect the earth lead first.  That way if your spanner touches the body it doesn't short out.  Once the earth lead is removed touching the body with the spanner doesn't produce loads of sparks.

This is only "best practice" but you are working on a Merc with Merc electrics.

Mick.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #34 on: October 25, 2014, 01:44:32 PM »
I hope nobody gets the impression that Merc electrics are "iffy".  They're not.  They are robust and most controls have at least one level of redundancy.  They are however, very complex and don't like to be messed with.  So the same rule applies.  If in doubt, don't.
M
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

seriph

  • Hero Member
  • *****
  • Posts: 845
  • Karma: +0/-5
    • View Profile
Re: SL Revalations
« Reply #35 on: October 25, 2014, 09:36:18 PM »
If your spanner touches the body when disconnecting the positive terminal, it will still cause a short
Steve

wishing we could get cars like these legally registered downunder

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #36 on: October 25, 2014, 10:04:28 PM »
Seriph

If there is only one battery once you have removed the earth lead there will be no short.  Two batteries with a common earth I don't know.  I'll stick my meter on things when we put the batteries back in.

Hmm, interesting.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #37 on: October 30, 2014, 09:41:06 AM »
The Furrari has an electrical problem at the moment.  This discharges the rear battery over a couple of days.  The rear battery looks after everything but the starter.  As tenpin and I have posted, care needs to be taken when jumping batteries in the SL.  Yesterday when The Furrari was at DNA we needed the roof down but the rear battery was to flat to lower it.  Remedy, start the car; the rear battery can then have another battery jumped to it to power the roof.
This works because the alternator produces 14 to 14.7 volts.  The jumper battery is at 12 volts so the battery charging module sees the voltage flow in the right direction with the front battery at the higher voltage than the rear, just as it does when running normally.
Result, no potential damage to the charging module.
Kalifornia tells me there are two upgrade charge controlling modules, the latest one is designed to prevent the problem caused by this reverse voltage but we don't have details of dates or part numbers.

I'm afraid this charging requirement transfers over to the West Coast, but at least you know how to treat the Merc charging system.

Mick.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Darren

  • Hero Member
  • *****
  • Posts: 831
  • Karma: +1/-0
  • If it don't fit cut it bash it weld it paint it
    • View Profile
Re: SL Revalations
« Reply #38 on: October 30, 2014, 08:11:24 PM »
I've got a Pheaton which also adopts the two battery scenario, When the vehicle is locked, the ecu's go into 'hybernation mode' this keeps the memory settings etc in the ecu's but draws minimal current from the AGM battery, perhaps this may be the problem you're having, the vehicle needs to sleep
D
Well, I'm into the 11th year of the project, could it be ready for Stoneleigh 2020, doubt it. The longest DNA build ever

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #39 on: October 30, 2014, 09:13:56 PM »
Dangerrous
I'm sure it's not a problem long term.  Some bits of trim aren't on back on yet so it's probably just some switch or sensor not made yet.  I'll start to worry if the problem persists when it's all back together.  In the meantime I'll just disconnect the battery when we don't need it.  We have two SL patern batteries and one of my caravan ( also known as the Hotel California) which can be connected with jump leads if we need to.
Thanks for the idea.  The problem is that Merc sparky things are very complex, far beyond a mechanical engineer like me.

Mick
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

DNA USA

  • Sr. Member
  • ****
  • Posts: 293
  • Karma: +0/-0
  • DNA Automotive USA @ www.DNAautomotiveUSA.com
    • View Profile
    • DNA Automotive USA
Re: SL Revalations
« Reply #40 on: October 30, 2014, 10:27:03 PM »
Can't wait to see pics of the Furrari WC towing the Furrari HC...

Dove US
DNA Automotive USA
A Series of Car Caves, LLC
Distributor for DNA Automotive in the USA
www.DNAautomotiveUSA.com
www.facebook.com/DNAautomotiveUSA

Comprehensive Self-Build Body Kits and Turnkey Conversions For BMW Z3, BMW M Roadster, Mercury Cougar, Mercedes-Benz SL, and Toyota MR2 MkIII Road

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #41 on: October 30, 2014, 11:13:31 PM »
DoveUS
Sorry mate, no can do.
The original concept was that The Furrari was fitted with a tow bar to tow The Hotel California.  Further research. ( trying to buy a tow bar) showed that because Merc say that due to the way the boot opens to suit the roof there is no type approved bar to suit the SL, let alone an SL that looks like a Furrari.
The days have gone when you could go get some angle or box section, bolt it together and then weld it.  These days, no type approval.  No type approval, it's illegal and no insurance.
Not a bad thing I suppose.  I've built many tow bars in the past with no problems but one of the lads in the motoring club I was in built one for his Mini and he left the bar and his trailor in the middle of the A5.  But then he always was mechanically challenged.
« Last Edit: October 31, 2014, 11:22:37 PM by Furrari »
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #42 on: November 15, 2014, 04:59:20 PM »
Not posted for some time cos I thought I'd posted most of the interesting stuff, but not all of it.

The SL has sensors that detect if the bonnet is not fully closed ( one each side) and put a message up on the dash if required.  ( it looked closed but wasn't)

This is transferred across to the West Coast ( one guess how I found that one out)

Join the West Coast crew.

Mick
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #43 on: March 17, 2015, 09:37:29 AM »
I never seem to stop finding new bits about the SL.  I previously posted about the side lights and the fog lights.

In a similar vein if you loose a front indicator light, the fog light works as the indicator ( don't know what happens if you loose a rear).  The rear indicator continues to work normally but the indicator warning  light on the dash flashes at twice the normal rate to tell you there is a problem.  A message also comes up on the speedo Comand system to tell you of the problem.

The ability to do this is carried over to the West Coast but depends on having fog light fitted.

Join the West Coast crew.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.

Furrari

  • Hero Member
  • *****
  • Posts: 2030
  • Karma: +1/-12
  • A wise man can control the stars
    • View Profile
Re: SL Revalations
« Reply #44 on: April 14, 2015, 06:12:27 PM »
Kal may have noticed this as well.
If you remove the airbag housing from the SL steering wheel you will see there are two airbag plugs.  If you hit something solid in the SL the sensor will detect how hard you have hit it and work out which air bag (or both) airbag to deploy to suit the impact.

This safety feature is carried over to the West Coast.
Not all problems can be solved with gaffer tape.  For those there is WD40.
Not even gaffer tape can fix stupid, but it can mask the sound.

If you can’t buy it or steal it you have to make it.