Bad battery - don't be fooled
Thread Starter
Junior Member
Joined: Jul 2007
Posts: 20
Likes: 1
From: Memphis
2016 GLC300 4MATIC
Bad battery - don't be fooled
First my 2002 C240 showed a "Lamp Sensor - Visit Workshop" fault, although I had no problem with headlights, and it starts & drives fine. Did find the wipers didn't work in rain sensing mode. I figured I needed to replace the lamp sensor.
Then a few days later, before I could look into the sensor issue, the transmission went into safe mode and had to drive home slowly in low gear. OBD2 pulled a P0702 fault - Transmission Control Sys Electrical. Starting was still fine and there was no low voltage warning. Load test on old battery showed low charge, but was inconclusive. Alternator tested fine during load test. Decided to replace original battery.
A new battery solved all problems - lamp sensor fault immediately cleared and transmission is back to normal. If I had acted on sensor and transmission faults, could have spent much more $$$. Wonder what the $tealer would have charged?
PS - during battery swap maintained voltage using charger and avoided all errors and resets normally encountered when battery is disconnected.
Then a few days later, before I could look into the sensor issue, the transmission went into safe mode and had to drive home slowly in low gear. OBD2 pulled a P0702 fault - Transmission Control Sys Electrical. Starting was still fine and there was no low voltage warning. Load test on old battery showed low charge, but was inconclusive. Alternator tested fine during load test. Decided to replace original battery.
A new battery solved all problems - lamp sensor fault immediately cleared and transmission is back to normal. If I had acted on sensor and transmission faults, could have spent much more $$$. Wonder what the $tealer would have charged?
PS - during battery swap maintained voltage using charger and avoided all errors and resets normally encountered when battery is disconnected.
Last edited by neilpilot; Mar 8, 2008 at 11:12 AM.
Super Member
Joined: Jun 2007
Posts: 502
Likes: 0
From: SOCAL
03 c240
MBWorld Fanatic!
Joined: Jan 2005
Posts: 2,848
Likes: 15
From: Orange County
2005 C Wagon (No snickering please!)
The dealer would jack up your trousers and rotate your wallet. Even if it was just a battery you would have paid so much more than calling Roadside. They replace the battery for free, and charge only for the battery. They don't charge an inflated price for parts, as is the practice at many dealers.
Member
Joined: Oct 2002
Posts: 82
Likes: 0
From: Southern California
C230 2.3 Manual Coupe
I did notice that I keep getting various malfunction codes just before my battery dies. A couple of weeks ago I had ABS fault and license plate bulb fault display came on. I didn't do anything since the display disappears after you turn off and restart the car again. My battery died afterwards after leaving it in the garage for too long. After recharging the battery the fault codes stopped appearing.
MBWorld Fanatic!
Joined: Jun 2002
Posts: 7,263
Likes: 169
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
I'm still on original battery...been getting it checked every few months...
maybe check it again today. 6.5 years on a battery. Wow.
maybe check it again today. 6.5 years on a battery. Wow.
Thread Starter
Junior Member
Joined: Jul 2007
Posts: 20
Likes: 1
From: Memphis
2016 GLC300 4MATIC
That's the point of my original post - I had absolutely no starting problems and no low voltage indications, just other problems that did not point directly to a bad battery.
Autozone said it showed a low charge and didn't recommend replacement, telling me that there could be another reason for the low charge. I decided to replace the 6 year old battery before looking for another cause of the lamp sensor and transmission faults, and the new battery solved both problems. I didn't have much to lose, since even if the battery wasn't the problem I knew it couldn't last too much longer.
MBWorld Fanatic!
Joined: Jun 2002
Posts: 7,263
Likes: 169
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Last time I had it checked they showed 600 CCA
thats less than the rated amount and down from the previous 650...
so likely I'm getting close to the time.
Maybe I should just bite the bullet..
but then, I also want to send the alt and SC out for rebuild...
for long term reliability, rather than dealing with breakdowns.
How much was the battery?
What kind did you get?
I'm quite impressed with the quality of the stock battery.
thats less than the rated amount and down from the previous 650...
so likely I'm getting close to the time.
Maybe I should just bite the bullet..
but then, I also want to send the alt and SC out for rebuild...
for long term reliability, rather than dealing with breakdowns.
How much was the battery?
What kind did you get?
I'm quite impressed with the quality of the stock battery.
Trending Topics
MBWorld Fanatic!
Joined: Jul 2005
Posts: 2,989
Likes: 0
From: San Jose, Bay Area
2002 C230 coupe , NOt THE AVATAR!!
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Thread Starter
Junior Member
Joined: Jul 2007
Posts: 20
Likes: 1
From: Memphis
2016 GLC300 4MATIC
Autozone Duralast 49-DL at $85. Specs 850 CCA and 1000 CA. I considered another MB battery, but MB roadservice might not have agreed that my battery was bad AND I wanted the car fixed quickly.
After I removed the battery hold-down bracket, I clipped my battery charger positive to the aux post and gounded it to the strut mount, and then removed the battery. About an hour later I was home after having my battery tested and buying the new one. Installed new battery, then removed charger. Absolutely no memory lost and no resets were required, and the transmission and lamp sensor issues were gone. Delay wipers are now working again.
Next day had Autozone load test alternator just to confirm there were no other problems.
After I removed the battery hold-down bracket, I clipped my battery charger positive to the aux post and gounded it to the strut mount, and then removed the battery. About an hour later I was home after having my battery tested and buying the new one. Installed new battery, then removed charger. Absolutely no memory lost and no resets were required, and the transmission and lamp sensor issues were gone. Delay wipers are now working again.
Next day had Autozone load test alternator just to confirm there were no other problems.
Member
Joined: Feb 2007
Posts: 180
Likes: 0
From: Long Beach, CA
'02 C230K Coupe
I replaced my last ~Nov. When it was at the dealer it sat for a few days and they couldn't start it... or so they said... *rubs chin*
MBWorld Fanatic!
Joined: Jul 2005
Posts: 2,989
Likes: 0
From: San Jose, Bay Area
2002 C230 coupe , NOt THE AVATAR!!
Newbie
Joined: Feb 2006
Posts: 2
Likes: 0
From: Temecula, Ca
'02 c240
Just had the battery replaced through the dealer for $135 - Free install. This fixed the Light Sensor issue and occasional SRS not available.
Most importantly it corrected an issue that I had been having recently with the transmission. Seems that it used to get stuck while in D on the first gear (safe mode?). After a while, I would have to stop, remove the key, and restart. The car would drive normal.
Most importantly it corrected an issue that I had been having recently with the transmission. Seems that it used to get stuck while in D on the first gear (safe mode?). After a while, I would have to stop, remove the key, and restart. The car would drive normal.
Junior Member
Joined: Jan 2004
Posts: 69
Likes: 0
From: Winnipeg, Canada
2002 C230 Coupe
Hi Guys,
I my car starting giving the lamp sensor warning a month or so ago but the sensor still worked so I thought nothing of it and ignored it. Then yesterday the car refused to switch out of (first?) gear and the engine light came on. I checked the engine code and it turns out it was code P0702. After reading the forums I decided to buy a new battery (Exide Performance Series 850 CCA/1000CA Type 49) as mine was original (7 years old) and on it's last legs.
After installing the new battery I no longer get the lamp sensor warnings, however the transmission issue still persists and the engine light/code came back as well.
Any ideas? Should I try charging the new battery and try again? No I need something other than a standard CANBUS code reader to get the car out of "Limp" mode? Could the alternator be dead? I'm only at 68k miles/110,000kms so I wouldn't think the alternator would be toast so soon.
Thanks in Advance,
Rich....
I my car starting giving the lamp sensor warning a month or so ago but the sensor still worked so I thought nothing of it and ignored it. Then yesterday the car refused to switch out of (first?) gear and the engine light came on. I checked the engine code and it turns out it was code P0702. After reading the forums I decided to buy a new battery (Exide Performance Series 850 CCA/1000CA Type 49) as mine was original (7 years old) and on it's last legs.
After installing the new battery I no longer get the lamp sensor warnings, however the transmission issue still persists and the engine light/code came back as well.
Any ideas? Should I try charging the new battery and try again? No I need something other than a standard CANBUS code reader to get the car out of "Limp" mode? Could the alternator be dead? I'm only at 68k miles/110,000kms so I wouldn't think the alternator would be toast so soon.
Thanks in Advance,
Rich....
MBWorld Fanatic!
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Thread Starter
Junior Member
Joined: Jul 2007
Posts: 20
Likes: 1
From: Memphis
2016 GLC300 4MATIC
Hi Rich,
Back when I changed my battery, the car then returned to normal. Trans returned to normal operation without having to doing anything special. I had borrowed a fault reader from a friend when I pulled the P0702 code, and I can't remember if I used his reader to clear the faults. It was a standard ODB2 tool.
When you changed the battery did you hod voltage on the power buss as I did (I used my battery charger), until the new battery was installed?
Its been 7 months since I changed the battery, and I've had no problems with light sensor, wiper control, transmission or any other codes or electrical issues.
Back when I changed my battery, the car then returned to normal. Trans returned to normal operation without having to doing anything special. I had borrowed a fault reader from a friend when I pulled the P0702 code, and I can't remember if I used his reader to clear the faults. It was a standard ODB2 tool.
When you changed the battery did you hod voltage on the power buss as I did (I used my battery charger), until the new battery was installed?
Its been 7 months since I changed the battery, and I've had no problems with light sensor, wiper control, transmission or any other codes or electrical issues.
Junior Member
Joined: Jan 2004
Posts: 69
Likes: 0
From: Winnipeg, Canada
2002 C230 Coupe
Hi Rich,
Back when I changed my battery, the car then returned to normal. Trans returned to normal operation without having to doing anything special. I had borrowed a fault reader from a friend when I pulled the P0702 code, and I can't remember if I used his reader to clear the faults. It was a standard ODB2 tool.
When you changed the battery did you hod voltage on the power buss as I did (I used my battery charger), until the new battery was installed?
Its been 7 months since I changed the battery, and I've had no problems with light sensor, wiper control, transmission or any other codes or electrical issues.
Back when I changed my battery, the car then returned to normal. Trans returned to normal operation without having to doing anything special. I had borrowed a fault reader from a friend when I pulled the P0702 code, and I can't remember if I used his reader to clear the faults. It was a standard ODB2 tool.
When you changed the battery did you hod voltage on the power buss as I did (I used my battery charger), until the new battery was installed?
Its been 7 months since I changed the battery, and I've had no problems with light sensor, wiper control, transmission or any other codes or electrical issues.
The lamp sensor error code did go away so the battery was definitely not working right. Just surprised the tranny issue is still there.
Right now my plan is to charge up the battery and try again tomorrow, failing that I'm not sure what to do barring having it towed to the dealer.
Rich...
Junior Member
Joined: Jan 2004
Posts: 69
Likes: 0
From: Winnipeg, Canada
2002 C230 Coupe
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
This all makes a lot if sense. 6 years is enough for a battery. I'm going to change mine at six years & not wait for trouble - Thanks
MBWorld Fanatic!
Joined: Jun 2002
Posts: 7,263
Likes: 169
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
I do recall Emrliquidlife had an error that put the car into limp mode until it was cleared. (Check engine light)
I started keeping an OBD tool in the car after I read that.
I started keeping an OBD tool in the car after I read that.
Junior Member
Joined: Jan 2004
Posts: 69
Likes: 0
From: Winnipeg, Canada
2002 C230 Coupe
. Cept in this case I cleared it and it came back, and is still stuck in first gear.Rich....
Junior Member
Joined: Feb 2008
Posts: 45
Likes: 0
-
The dealer would jack up your trousers and rotate your wallet. Even if it was just a battery you would have paid so much more than calling Roadside. They replace the battery for free, and charge only for the battery. They don't charge an inflated price for parts, as is the practice at many dealers.
Junior Member
Joined: Jan 2004
Posts: 69
Likes: 0
From: Winnipeg, Canada
2002 C230 Coupe
Rich...
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
