NeilsSmartOnAegina

Smart for two 450 Diesel three bars flashing.

41 posts in this topic

Wiring diagram rear fuse and relay box.pdf

 

I suggest a work around to allow you to use the car.  Not perfect but should work although you need to exercise care not to operate starter whilst engine is running or in gear.

 

I suggest to fit a push button switch to operate starter solenoid.

 

You need a 2.5 mm2 cable of sufficient length, two male crimp terminals and a push botton starter switch or similar that is good for minimum 25 A.

 

Pull out relay K3 in fuse and relay box under seat.  Connect the male crimp terminals to terminals 30 and 87 of relay socket for relay K3.

 

I will provide a photo showing exactly where to connect.

 

Instead of switch you can use a piece of wood and two wood screws.  Place the screws a safe distance apart for example 30 mm.  Tie end of the two cables to each screw.  Use a piece of metal to bridge the screws and thereby start your Smart. 

 

   

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Can you tell me can I get to the starter motor terminals, these are the only thing I have not been able to check?

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Oh just made the cable as you suggested and I just get a click and no movement from the engine

 

thanks for the ideas though as I am running out of ideas and could try anything...

 

 

 

 

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Can you measure battery voltage when you attempt to start hot wired as I suggested?

 

Turn on head lamps whilst you  attempt to start. I bet a good pint of ale  they will go rather dim. 

 

Just a click from starter solenoid points to bad battery or bad contact somewhere. Also explains why dash board lights flash and relay keeps clicking continuously.  

 

Therefore start with battery, battery poles, earth straps etc. 

 

 

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A wee tool tip regarding battery testers. 

 

I have two such tools. 

 

An old style with analogue meter and a large resistor element big enough to bake bread.  Works fine but not always easy to interpret battery condition. 

 

My second brand new tester is just perfect. 

A Lancol Micro-200 Pro digital battery tester. Came all the way from China and only cost just below £18 with delivery. 

Tests battery, charging system and starter. 12 and 24 Volt systems. 

Measures internal resistance of batteries, battery voltage and cold cranking current to any standard like SAE, DIN, EN, JIS etc etc. 

 

The same day as this tool arrived I visited two local garages and tested their junk replaced batteries. Drove home with four perfectly good batteries. One of them, a large Varta tested to 105% health. 

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hello again Tolsen,

Well I have another update for the saga...  maybe you can help.   I have a brand new battery and it is fully charged. but on starting it just clicks..   So today I jacked up the back wheel and removed the cover covering the belts on the engine. I have put a socket on the crank and turned this no problem, I then went under and did the same for the alternator and starter and all is free and not ceased. So I asked the wife to try to start the engine whilst I had a mirror under the engine and I noticed...   The click still happened but as it did then engine crankshaft and all the other wheels shift about 5mm on every click...   Sorry for all the questions but the hammers are getting bigger....  Neil

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Starter!?

 

Mine went kaput 3 leap years ago.  Road salt had disintegrated the bare heavy gauge copper wire from starter solenoid to starter brush gear.  You can see this bare wire in first of below photos showing the starter fitted in a diesel Smart 450.

 

0300-001-106-025-3.jpg

 

0300-001-106-025-1.jpg

 

0300-001-106-025-2.jpg

 

0300-001-106-025-4.jpg

 

0300-001-106-025-5.jpg

 

Above described heavy gauge wire disintegrating is the second most common problem with starters on the 450.  Main problem is bad contact on spade connector at starter solenoid which in your case still appears fine since you can hear starter solenoid clicking.

 

Me being a born miser and living in Aberdeenshire did not wish to waste money on a new starter so opened mine up and replaced the disintegrated wire.

 

Removing starter will take a few hours and may easily take a full working day for some that has never attempted this before.

 

It is therefore essential that we now correctly diagnose the problem.

 

You know how to operate starter from relay socket.  Are you getting same single click from starter when operating starter from relay socket?

 

To rule out negative earth leads and straps, run a jump lead from battery negative to engine or transmission somewhere and repeat test operating starter from relay socket.

 

Read off battery voltage when doing both above tests.  No load battery voltage and battery voltage when starter solenoid is energized.

 

Starter can only be replaced when subframe is lowered sufficiently to provide access or the whole subframe assembly complete with engine, transmission and suspension is lowered and wheeled rearwards behind the chassis.  The latter is more complicated as brake line, cables and hoses must be disconnected as well.

 

Lowering of subframe can be done without the special long lowering bolts (available to trade only from Smart/ Mercedes dealer) by fitting the long rear subframe bolts in forward holes and lowering subframe whilst guided on these long bolts.  You then need two suitably strong and long wooden sticks to support rear end of subframe as unwise to leave rear end of subframe supported on a trolley jack.  May cause damage to both chassis, subframe and bolts if trolley jack dropped due to creep, leak or accidental release.  

 

Starter is held on two long male Torx headed bolts screwed in from the left side hidden under intercooler support cradle.  These two long bolts screw into threads cut in starter itself.  Intercooler support cradle need be released and slightly lifted to provide access to starter bolts.  Remove rear left road wheel for improved access.  Rear left wheel arch may have to come out too but I cannot remember if I did.

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It is quite likely there is an internal fault in starter causing a rather high voltage drop when starter solenoid is energised.  That is why I like to see voltage readings.

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The small incremental rotation you see is possibly just caused by bendix drive in starter when solenoid engages starter pinion with flywheel tooth ring. 

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Starter could also be seized and in that case there will be a rather high power draw and voltage drop sufficient to make havoc with dash board lights and control unit behaviour.

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Starters now a days are cheap, IMHO, rebuilt and even new....$220 Canadian for me with warrentee......cheaper if without and cash...lol.
IMHO, unless you also are a serious miser as Tolsen admits he is, just buy one and while you are trouble shooting with starter out and YES it's a serious pain in the arse to remove, simply install a new one while doing so.   Just disconnecting the wires on the back of the starter is a challenge and a mental one also.!!!

Again....spend the money on this if you are getting to the point of thinking about the starter.....and seeing as you are basically in the right location go after the water pump, and thermostat and alternator....IF you can afford....there is an upgraded thermostat mod to research again if you want to go this way.
Also if you do not use air conditioning or think you never will, research removing a mile of heater hosing and also the EGR system as it'll free up some space in the crowded engine compartment...lol.....It's never ending this modification sickness...lol.

OR....you can do what I and Sydney have done, while going after the starter decided it's far easier to remove the sub frame and do it all now.....a complete rebuild of everything...lol.....but this is where it does get expensive...!!!!

Seriously though, just buy a new starter and repair any wiring when doing so, and then think what else is near this area and do I ever want to get this deep again.   My motto is do it now, do it once....and do it better than new.   That way it's a completely reliable vehicle....that is if you are thrilled with the Smart in the first place....Many are.

 

 

Sorry Tolsen....I spend big when required and then kick in my cheap ass when not so important......to each their own..

 

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There is no point replacing parts Nelly-Willy but always worth while doing preventative maintenance and simple cost effective improvements.

 

  1. Blank off exhaust supply to EGR valve.  Results in much less smoke and less soot contaminating the oil.
  2. Regularly inspect wiring to transmission and make sure wiring is properly clamped.  Result is much less chance of chafed wiring that is likely to cause breakdown.
  3. Grease socket clutch release for where clutch actuator rod enganges.  Results in less wear and less chance of socket punch through which require a costly removal of transmission unless you do the work yourself.
  4. Clean and grease clutch actuator.  Clean areas where rubber boot seals against clutch actuator body and rod.  Apply silicone grease or red rubber grease to these areas. Results in no more water and dirt entering clutch actuator provided done right.
  5. Grease threads in transmission where bolts that hold clutch actuator in place fit.  Makes it easier to remove without the bolts snapping off.
  6. Correctly preload clutch actuator at least annually.  Grease socket same time.  Results in less wear and smother gear changes.
  7. Fit free wheeling pulley on alternator.  Gives faster gear changes changing up and therefore quicker acceleration.  Also much smoother idle.
  8. Fit standard Smart 451 springs on front and standard Smart Roadster 452 springs on rear.  Results in higher road clearance and more comfortable ride.  Also much less chance of spring break.

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2 hours ago, tolsen said:

There is no point replacing parts Nelly-Willy but always worth while doing preventative maintenance and simple cost effective improvements.

 

That is how it starts, I always make things like new or better just to save me from redoing things a week or month down the road while on side of road...lol

It's all personal preference and IF you can afford to spend it at once while doing the main issue at hand.   Money talks as they say.......the rest walks....I don't like walking...lol.

On this vehicle with it being such a chore and pain in the arse to work on, this mentality is best.....unless you like torturing yourself working in a space built big enough for a feeler gauge and not much else around the engine etc.
 

Also isn't it Willy Nilly....lol

 

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