SL/R230: Jump start/electrics problem
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SL500 R230
Jump start/electrics problem
Having some problems with the sl at the moment.
I havent driven it in a couple of weeks. The fob no longer opens the car. I used the key and gained access. The key will slot into the ignition but will not turn. I thought it could be the front battery but attached jump leads and nothing happened. I thought it might be the rear battery. However I cant access the boot. The key wont turn and open the boot. Erm...help? Any ideas?
Cheers
I havent driven it in a couple of weeks. The fob no longer opens the car. I used the key and gained access. The key will slot into the ignition but will not turn. I thought it could be the front battery but attached jump leads and nothing happened. I thought it might be the rear battery. However I cant access the boot. The key wont turn and open the boot. Erm...help? Any ideas?
Cheers
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
You really ought to be able to get into the boot, since it is purely mechanical using the key in the lock.
If the key won't turn in the ignition switch, then possibly the switch is not powered. Check for a blown fuse in blocks F32 and F33. Details are in the PDF file attached to this post.
If the key won't turn in the ignition switch, then possibly the switch is not powered. Check for a blown fuse in blocks F32 and F33. Details are in the PDF file attached to this post.
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SL500 R230
You really ought to be able to get into the boot, since it is purely mechanical using the key in the lock.
If the key won't turn in the ignition switch, then possibly the switch is not powered. Check for a blown fuse in blocks F32 and F33. Details are in the PDF file attached to this post.
If the key won't turn in the ignition switch, then possibly the switch is not powered. Check for a blown fuse in blocks F32 and F33. Details are in the PDF file attached to this post.
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No, you cannot jump from the front battery. So the metal key does not turn at all in the trunk lock? Or it does not open when turned? Note that once the key is turned, you still have to pull the handle to release the latch.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Yes. Once the ignition key is turned you have c. 30 seconds to engage the starter. If that time period has elapsed, then you must turn the key back to position zero and try again.
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SL500 R230
I can't jump the car from the front battery under the hood? I need to jump from the rear battery in the boot/trunk?
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SL500 R230
Confused now as @Rudeney said I cant jump start the car from the front battery and you say I can. The manual says I can, but doesnt specify if thats possible if the rear battery is flat. Maybe I need to get into the boot and charge the rear battery first with a booster box and then when thats up and running I jump the car from the front battery with another car?
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
K57 will remain energized for about 5 minutes after the engine starts. If it were me I might wait for the relay to de-energize before removing the jumper cables after a successful start.
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SL500 R230
Since the state of the rear battery charge is immaterial, the manual does not mention it as a factor.
No. Refer to page 31 of the PDF file mentioned in my first post and note that the K57 relay connects the front and rear batteries together in parallel in the case where the rear battery is flat.
K57 will remain energized for about 5 minutes after the engine starts. If it were me I might wait for the relay to de-energize before removing the jumper cables after a successful start.
No. Refer to page 31 of the PDF file mentioned in my first post and note that the K57 relay connects the front and rear batteries together in parallel in the case where the rear battery is flat.
K57 will remain energized for about 5 minutes after the engine starts. If it were me I might wait for the relay to de-energize before removing the jumper cables after a successful start.
Will attempt this in the evening and report back!
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
I presume the SL500's engine will be running; if so, then yes -- there should be adequate power to open the trunk. But if a fuse is blown the engine may not start.
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My understanding is that if the rear consumer battery is dead that you cannot "jump" from the front starter battery to fix that - you have to jump or charge the rear consumer battery. Now, if you turn the key and the engine won't crank, or is too slow to turn over, then you could jump start the front battery to fix that problem. Having said that, there were some changes to the BCM that allow the front starter battert to "supplement" a low rear consumer battery, and vice-versa, but I think that was on the SL550, not the S500.
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Further, jumping from the rear needlessly exposes the vehicle electronics to voltage spikes that can cause damage. On my car a plastic cover which attaches above the positive post of the rear battery cautions to ONLY jump-start from the front battery.
There were no such changes. From the beginning of R230 production the K57 relay connects the two batteries in parallel in the event of the rear battery being below about 10.8 volts (weak). If the front battery is weak, then the vehicle can not be started unless a little trick is employed: disconnect the rear battery, turn the ignition key to position 2, and within 30 seconds reconnect the rear battery and start the engine.
Last edited by bobterry99; Feb 8, 2018 at 05:05 AM.
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SL500 R230
Ive run into another problem (these are really adding up!!)
I cant seem to open the hatches behind the seats. Either of them. I need to get access to the fuse box there and cant open them. They seemed to be fine before this problem. The same is true of the glovebox as well.
Any suggestions?
I cant seem to open the hatches behind the seats. Either of them. I need to get access to the fuse box there and cant open them. They seemed to be fine before this problem. The same is true of the glovebox as well.
Any suggestions?
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From: amarillo texas
2003 sl 500
When you locked the car it locks all the stuff you mentioned plus the consol. Really need to get the PSE pump some power(rear batt.) to undo the lock ups. Need to get the trunk open somehow. I cannot imagine why the key will not open the darn trunk.
moretech
moretech
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SL500 R230
Once I make it into the boot, should I use a particular charger? (i cant jump the front until I get access to the cubby holds behind the seats, which needs the rear battery to be working). Im hoping to get the boot open and charge the battery giving me access to the unlocking function via the key which I can then use to change any fises and then hopefully jump the car (from the front battery)
Something like this be ok to charge the rear?
http://www.halfords.com/workshop-too...attery-charger
Or this?
http://www.halfords.com/workshop-too...les-up-to-2-0l
Im after the quickest charging option if there is a choice as I have it booked it to see a MB specialist in about 24 hours and will only be able to start charging in around 10 hours.
Thanks guys.
Something like this be ok to charge the rear?
http://www.halfords.com/workshop-too...attery-charger
Or this?
http://www.halfords.com/workshop-too...les-up-to-2-0l
Im after the quickest charging option if there is a choice as I have it booked it to see a MB specialist in about 24 hours and will only be able to start charging in around 10 hours.
Thanks guys.
Last edited by Indyvidual; Feb 9, 2018 at 03:50 AM.
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From: amarillo texas
2003 sl 500
I would remove the rear batt and have it charged by a local shop and checked for proper operation. Then reinstall it and see where things are. If AGM type batt I notice the charger in the ad cannot do an AGM battery. I do not believe a rear battery should ever be jumped. Even easier just buy and install a fresh rear AGM battery. Really hard to check electrical headaches without knowing what the battery condition is. You could while the rear batt is out do the same to the front battery and see if it will hold a charge. Remember front batt goes in before the rear battery when both are out. Keep us posted how it all comes out.
moretech
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Not true. The vehicle can unconditionally be jumped from the front battery, but jumping from the rear can be problematic. For example, if the front battery is weak and the rear is not, then the power from the donor vehicle's alternator won't reach the SL's front battery or starter motor, and the effort is pointless.
Further, jumping from the rear needlessly exposes the vehicle electronics to voltage spikes that can cause damage. On my car a plastic cover which attaches above the positive post of the rear battery cautions to ONLY jump-start from the front battery.
There were no such changes. From the beginning of R230 production the K57 relay connects the two batteries in parallel in the event of the rear battery being below about 10.8 volts (weak). If the front battery is weak, then the vehicle can not be started unless a little trick is employed: disconnect the rear battery, turn the ignition key to position 2, and within 30 seconds reconnect the rear battery and start the engine.
Through MY2008: http://benzbits.com/R230/BatterySystem.pdf
MY2009+: http://benzbits.com/R230/BatterySystem2009.pdf
I think that as of MY2009, the system was altered so that both front and rear batteries can "help" each other, but prior to MY2009, the only option was that a weak consumer battery could be supplemented by the starter battery, but not vice-versa. I could be wrong here, but that's how I have always interpreted the difference. .
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Nothing I read suggests this is the case. Operation of the K57 relay is solely dependent upon the "on-board power supply voltage" and never the starter battery voltage. Note that in this document the rear battery is referred to as the "on-board electrical system battery".
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This is what I was reading:
So what you are saying is that the "undervoltage" only applies to the consumer battery, and not the starter battery? I assumed since there was no distinction made in that paragrach that it applied to both.
As for charging the consumer by connecting to the starter battery, I don't see that working unless the BCM has switch on relay K57 to put the two batteries in parallel. It does that in an undervoltage situation, but I am not sure what that is. The WIS doc mentions that after the BCM cuts-in the starter battery, it won't cut it out until voltage reaches 12.5v for 3-7 minutes (depending on the severity of the undervoltage situation). I do see it mentioned that Stage 1 low voltage is M< 10.6v. Maybe that's the threshold? If so, that means if the consumer battery voltage drops below 10.6v, and the K57 relay is activated to put the batteries in parallel, the you could charge the consumer battery via connection to the starter battery.
Control of battery cutoff relay function sequence
The battery cutoff relay is controlled depending on the state of the
on-board electrical system. Depending on the state of the on-board
electrical system, the on-board electrical system battery and the
starter battery remain separated by the battery cutoff relay or are
connected in parallel.
A distinction is made between the following on-board electrical
system states:
- Normal starting mode
- Normal mode
- Emergency starting mode
- Emergency mode
- Shutoff phase
If there is no undervoltage, the on-board electrical system battery and
starter battery are separated (normal and normal starting mode).
If undervoltage is detected, the system switches to emergency and
emergency starting mode. The on-board electrical system battery and
starter battery are connected in parallel by the battery cutoff relay.
The battery cutoff relay is controlled depending on the state of the
on-board electrical system. Depending on the state of the on-board
electrical system, the on-board electrical system battery and the
starter battery remain separated by the battery cutoff relay or are
connected in parallel.
A distinction is made between the following on-board electrical
system states:
- Normal starting mode
- Normal mode
- Emergency starting mode
- Emergency mode
- Shutoff phase
If there is no undervoltage, the on-board electrical system battery and
starter battery are separated (normal and normal starting mode).
If undervoltage is detected, the system switches to emergency and
emergency starting mode. The on-board electrical system battery and
starter battery are connected in parallel by the battery cutoff relay.
As for charging the consumer by connecting to the starter battery, I don't see that working unless the BCM has switch on relay K57 to put the two batteries in parallel. It does that in an undervoltage situation, but I am not sure what that is. The WIS doc mentions that after the BCM cuts-in the starter battery, it won't cut it out until voltage reaches 12.5v for 3-7 minutes (depending on the severity of the undervoltage situation). I do see it mentioned that Stage 1 low voltage is M< 10.6v. Maybe that's the threshold? If so, that means if the consumer battery voltage drops below 10.6v, and the K57 relay is activated to put the batteries in parallel, the you could charge the consumer battery via connection to the starter battery.
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SL500 & GL450
Bobterry99 & Rudeney, I was told that there is a risk of damage to the BCM if jumpstarting and was advised to never jump start, but rather remove the starting battery and charge it independently. Was that incorrect advice??? Once the car is started, then the BCM will allow for charging the consumer battery, presumably giving access to the trunk. I defer to both your superior knowledge of the system, so your advice would be most appreciated. Thankfully I've not yet run into a situation of having a dead starting battery, but should I, I'd like to know if there really is any risk to the BCM through jumpstarting the front battery. As finicky as the R230 is to voltage fluctuations, I'd tend to err on the cautious side. Heck, when I'd previously thought about this potential I'd decided that even if this were to occur in the field, I'd preference removing the front battery and installing it in the donor/ jumpstarting vehicle and letting it's charging system apply a charge then before reinstallation, but realise that I'm a bit of a hypercondriac when it comes to exposing the R230 to unusual voltage spikes. I'm really interested in your input(s).
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SL500 & GL450
The key turns in the boot lock. It turns 90 degrees anticlockwise and about 45 clockwise. I havent really applied much pressure. Ill add a bit of pressure and try to get the lock to 90 degrees clockwise and pull the handle to see if it will open.
I can't jump the car from the front battery under the hood? I need to jump from the rear battery in the boot/trunk?
I can't jump the car from the front battery under the hood? I need to jump from the rear battery in the boot/trunk?
https://mbworld.org/forums/clk-class...rill-lock.html
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Obviously, if you remove the battery from the vehicle for charging, then you eliminate any worries about damaging the BCM electronics. According to WIS< the proper steps for battery disconnection is disconnect the consumer battery first, then the starter battery. And to reconnect the starter battery first, then the consumer battery. In other words, only work with connecting and dicconnectiing the starter battery once the consumer battery is disconnected.
Having said that, it is fine to charge the consumer battery without disconnecting anything. In fact, many people keep connect a C-Tek charger on theirs so the consumer battery does not drain after several days (or weeks or months) of being garaged.
Regarding the hard key mechanism on the trunk lock, yes, it does just move a plastic lever into the mechanism, but that plastic level allows the handle to then unlatch the lock. In other words, you insert the hard key in the lock, rotate it counter-clockwise, and while holding it there, squeeze the handle. The latch should then open - no electricity or pneumatic pressure needed.
Having said that, it is fine to charge the consumer battery without disconnecting anything. In fact, many people keep connect a C-Tek charger on theirs so the consumer battery does not drain after several days (or weeks or months) of being garaged.
Regarding the hard key mechanism on the trunk lock, yes, it does just move a plastic lever into the mechanism, but that plastic level allows the handle to then unlatch the lock. In other words, you insert the hard key in the lock, rotate it counter-clockwise, and while holding it there, squeeze the handle. The latch should then open - no electricity or pneumatic pressure needed.
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
I have jumped an R230 once and other modern Mercedes perhaps a dozen times with no ill consequences. It's my belief if proper procedure is followed there is very little risk.
Last edited by bobterry99; Feb 13, 2018 at 12:03 PM.
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Bob, one thing I am unclear about is this: Does K57 cut in if the car is just sitting there and voltage drops below 10.8, or would it only cut in with the ignition on? That would be important for the OP to know when trying to "boost" the consumer batter in order to open the trunk.
Also, I agree 100% with you on the car being designed for the possibility of jump starting. I hear so many people claiming that jumping will blow electronics and that's just plain wrong. Proper jump starting or charging won't damage anything. I've probably jump-started at least 100 MBZ cars and not damaged a single one. One thing that does happen is that a dead battery can act like a giant resistor so that jump starting won't provide enough amperage to the starter. In that case, disconnecting the dead battery works like a charm (I had to do that many times for cars sitting in the storage lot).
Also, I agree 100% with you on the car being designed for the possibility of jump starting. I hear so many people claiming that jumping will blow electronics and that's just plain wrong. Proper jump starting or charging won't damage anything. I've probably jump-started at least 100 MBZ cars and not damaged a single one. One thing that does happen is that a dead battery can act like a giant resistor so that jump starting won't provide enough amperage to the starter. In that case, disconnecting the dead battery works like a charm (I had to do that many times for cars sitting in the storage lot).
