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Solved - Strange challenge with alternator and when using keyless go with cold start
Dear all,
This is about W220, 320CDI, year 2003
When the car is cold and I try to start the car with the KLG system it reacts like there no power. Some times it’s normal to the start position, and when it try’s to turn the motor it goes of after 3-4 seconds like there no power and it does not start the motor. Other times it’s only try to take the steering wheel down and stops. At the hole time when it does this challenge it looks like in the driver display that it looses power, after 2-3 attempts it’s totally black in display. Even the normal key can’t start the car, it’s saids click click click.
Then I wait 1 hour, the car starts with the normal key, shut the car of and now it’s starts normal with the KLG system 😀
Please help me, what do you think the challenge could be? I have just replaced the EIS.
Last edited by DK14; Feb 19, 2020 at 04:10 AM.
Reason: New topics
Possible problem causes include:
- Battery is undercharged or undersized.
- Battery is intermittently failing.
- Poor connection on the main power circuit - Either battery terminal; ground terminal to chassis connection; faulty main fuse connection behind the trunk lining forward of the battery; faulty fuse connection at the main pre-fuses under the right front carpet floor panel.
The W220 does not usually have an auxiliary battery - I do not know whether the Diesel cars do in your market area or not.
The batteries in the key fob have no effect on starting the car - that power is furnished inductively from the EIS. If the inductive power is faulty, the car will not start, but the power to the entry movements or the display is not usually present then lost.
Possible problem causes include:
- Battery is undercharged or undersized.
- Battery is intermittently failing.
- Poor connection on the main power circuit - Either battery terminal; ground terminal to chassis connection; faulty main fuse connection behind the trunk lining forward of the battery; faulty fuse connection at the main pre-fuses under the right front carpet floor panel.
The W220 does not usually have an auxiliary battery - I do not know whether the Diesel cars do in your market area or not.
The batteries in the key fob have no effect on starting the car - that power is furnished inductively from the EIS. If the inductive power is faulty, the car will not start, but the power to the entry movements or the display is not usually present then lost.
Thanks both for your fast answers 👍🏻
The main battery is 10 months old and the best quality and correct size from Varta. Every time the car is home, it stands with maintenance charger on.
I looked at the fuses under the carpet for some months ago and they looked good.
Where is the fuse in the trunk located?
Maybe I should give the battery a new negative cable.
Why do i not have the challenge when using the normal key? and why does the car shuts down?
'00 S320 W220, '98 A160 W168/ sold in 2005 '86 260 E W124 '90 260E W124
Check the battery charge and voltage levels. Stand still 12.4 V Running 14.0V, starting the engine >11V. The failures you are experiencing is 90% a weak battery, especially when it's cold outside. W220's only have one battery
Check the battery charge and voltage levels. Stand still 12.4 V Running 14.0V, starting the engine >11V. The failures you are experiencing is 90% a weak battery, especially when it's cold outside. W220's only have one battery
thank you Bamberger.
But why is there no problem when starting with the key?
Check the battery charge and voltage levels. Stand still 12.4 V Running 14.0V, starting the engine >11V. The failures you are experiencing is 90% a weak battery, especially when it's cold outside. W220's only have one battery
just tested and the KLG worked fine 🤣
stand still 12,4V
ignition on 11V
when start it drops down to 10V
After it goes op to 11,8V then I give it 1500rpm and it goes to near 14V. This challenge I never figured out what the challenge is. New alternator, cables fine to right side, maybe it’s the Modul there.
'00 S320 W220, '98 A160 W168/ sold in 2005 '86 260 E W124 '90 260E W124
Some comfort functions will be shut off when low voltage shows. KLG is one of them. Anyways, 11V at ignition on w/o engine running, is suspicious. As well that >14V will only be reached at >1.500rpm is not quite right. Maybe your glow plugs causing the problem, as soon they engage at cold temperatures. Or the alternator does not charge sufficiently?
Some comfort functions will be shut off when low voltage shows. KLG is one of them. Anyways, 11V at ignition on w/o engine running, is suspicious. As well that >14V will only be reached at >1.500rpm is not quite right. Maybe your glow plugs causing the problem, as soon they engage at cold temperatures. Or the alternator does not charge sufficiently?
thank you Bamberger.
When the car is warm the alternator starts at much lower rpm. My glow plugs are from 18.10.19. The alternator works totally normal when it’s “started”
This sounds like a problem with the alternator, its wiring, or the main power circuits discussed earlier.
With a standing voltage of 12.5 vdc (which is still just a bit low) on a good battery, the voltage should stay at 12.5 when you turn the switch on. Either you don't have enough battery power, or it isn't getting to where it needs to be. The voltage should increase as soon as the engine starts - having to rev the engine up indicates a problem with the alternator or the wiring - my money is on a wiring fault, and I would start under the passenger floor carpet.
'00 S320 W220, '98 A160 W168/ sold in 2005 '86 260 E W124 '90 260E W124
Not that I would know of such a fuse there. https://www.motor-talk.de/forum/akti...hmentId=754992
These are the fuses in the passenger side foot well. Only available in German, but pretty much self explanatory, I think.
Dear all, there is a fuse in the back, right side. A 60amp and 100amp. I broke it when I should control it, so I replaced them. Simultaneous I made a new ground from battery to the chassis and clean the others. This help a little, but I am not finished. Now I have to move forward. I will write back 💪🏻
Dear all, I have now controlled the fuses in back and in front, they are all fine. I have made a new minus head cable from the battery to chassis and from motor to chassis. I have replaced the alternator and measure out the to cables from alternator to the right from SAM. The car still make this funny thing with the alternator only starts at 1200-1500rpm.
stand still 12,4V
ignition on 11V
when start it drops down to 10V
After it goes op to 11,8V then I give it 1500rpm and it goes to near 14V. This challenge I never figured out what the challenge is. New alternator, cables fine to right side, maybe it’s the Modul there.
Reading this again, I think the standing voltage is too low. Is standing voltage with the engine running? When the engine is running, the voltage should be around 13.6V or almost 14V.
Reading this again, I think the standing voltage is too low. Is standing voltage with the engine running? When the engine is running, the voltage should be around 13.6V or almost 14V.
when you have pressed the gas pedal it goes to 14,1 volts
A "standard" alternator needs "excitation voltage (power)" to begin generating electrical power, as the standard units are not fully self-exciting. However, most alternators will eventually build sufficient self-exciting power when the RPM gets high enough. On standard units, the excitation power was furnished thru the ALT (charging) light. If the bulb burned out, there was no excitation power furnished to the alternator, and most units would eventually self-excite when the RPM got high enough, and some units would not.
It sounds as if your alternator is not getting any excitation power. Again, I am not familiar enough with the W220 system to give you any real help...
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