stykshooter

Car has been sitting for 8 months with a trickle charger but it went bad, it was old.. Of course when I tried to start no lights on dash all dead. After a quick check both batteries were dead. Though it would be an easy fix so I replaced both batteries, starter battery 26 months old but the consumer battery was the original. I'm almost positive I replaced in correct order. After installing new batteries dash lights up radio comes on & seems that all is ok, get the offline message, it goes away after a bit. Still will not turn over, starter was replace about 10 months ago.

So my troubles begin, I have a MB11 ICarsoft & under System Diagnosis I have 22 DTC with the same message as pictured
Can Communication of Control Unit (22 different units) is in single wire mode ( Can bus Low)


FYI this has been my daily driver & has 185K, I had a family emergency that had me park it out of state.


Listed below are the 22 different units with the same message ??
Rear Sam
EZS
IC
OCP
ESA
DCM-FR
DCM-FL
BNS
ESA
AAC
Pass-Side Sam
HSW
Driver-side Sam
Command
SCM
LCP
PTS
AB
Keyless Go
Tele-Aid
TPC

Noir230

The section about batteries in the owner's manual (at least for my year) states that the ESP and windows must be re-synchronized and that battery cables must be reconnected in a specific order. Did you try those? I followed them when I swapped out both of my batteries and had no problem.

stykshooter

Thanks for the reply, I've reconnected batteries as manual recommended. I do have the ESP (white light) warning message but I believe I need to have the car running to reset that warning light.

bobterry99

I'll guess that your charger damaged electrical component(s) which may include the ignition switch. If the rear battery is okay, you should not be getting the "offline" message at all, and the fault codes you see may be a faulty module.

When you twist the key with the transmission in park or neutral the ignition switch sends a CAN message to the engine management controller which then actuates a small relay that in turn actuates the starter solenoid. My guess is that CAN message is not being sent due to a faulty ignition switch -- your iCarsoft unit may be able to check the status of that message. You'd have to check the electrical circuit from the engine management controller to the starter solenoid with a multimeter.

I don't believe any of these can cause your starting problem. All of those modules are on the body CAN. Normally communication is over a pair of wires; yours is communicating over one. Communications still occur albeit at a slower rate. To troubleshoot this problem I would unplug modules until I determined which one(s) was causing the problem -- when the problem module or modules are removed the CAN faults will disappear. I can offer more details but will only do so if requested.

stykshooter

Thanks bobterry99 I'm definitely in need of advise & help.


"offline" message did go away within minutes of battery being reconnected...


I access EIS- Electronic ignition switch and found "no" DTC's & if I remember I've never found a code in that section.
So if the switch sends a message what controller tells the relay to activate ??


Didn't think those 22 DTC's would be a starting problem.

bobterry99

The engine management controller activates the relay.

When an ignition switch fails it often gives no fault codes.

Attached is a diagram of the CAN network and the CAN B connectors. You can see that all modules on CAN B plug-in to one of three connectors: X30/15, X30/16, and X30/17 with a pair of wires colored brown and brown/red. It also shows /15 is linked to /16 by a pair of wires colored brown and brown/black, and /16 links to /17 with a similar pair.

I would remove /17 from the network by unplugging its link to /16. If you check faults again and the the single-wire problem is gone, then you know one or more of the modules plugged into /17 or its wiring is the problem; next you would plug /17 back into the network and then repeatedly unplug a module from /17, check faults, unplug a module, etc., until you found which one was causing the fault in the network. If removing /17 from the network didn't clear the single-wire problem, then you would remove /16 from the network and proceed as described above for that connector. If /16 is okay then you would proceed in the same manner with /15.

stykshooter

Makes sense & if 17 is disconnected & faults are gone will the car start, not that I'll drive just curious ?? I take on that project tomorrow afternoon, thanks I'll keep you updated

bobterry99

I'm doubtful.

Seen on the diagram are two CAN networks: "B" and "C". The drivetrain is on CAN C, and you don't appear to have any faults there.

stykshooter

Didn't get a chance to tinker today. So in theory EIS tells the ECM to activate a relay.... but it checks the key, brake switch & maybe the alarm ??

Rudeney

My guess is bad EIS. That "single wire mode" error is indicative of that.

bobterry99

It checks the transmission range for certain (P or R). It does not check the brake switch. The key is checked when inserted into the switch, so if the key turns it is okay. With a Star Diagnosis computer the state of the prerequisites is shown under an "Actual Values" menu for the engine management controller.

Tracking down the CAN error may show that the EIS can not establish two-wire communication with any module on CAN B, and I believe that would be sufficient evidence that the switch is causing the no-start problem and should be replaced. The ignition switch is N73 and shown in the diagram posted earlier.

stykshooter

Well after crawling around inside & checking xconnectors no error cleared after unplugging individual data bus wires. I removed the EIS which I'm hoping is the issue but can these be rebuilt or repaired.
I live 75 miles from my indy so I'm hoping to find something that can be plug & played. I believe these modules have to be programmed or married to ECM but if a new is purchased can it work so I can take to an indy.

Rudeney

I have heard of some people cleaning the connectors on the EIS and having some relief. But I think the failure is actually in the circuitry itself.

Ghostty

You are right, EIS module has to be programmed to work with the new vehicle. also the keys will need to be reprogrammed to be recognized by the new EIS module. Some indy shops could actually do this swap, but i decided to go with the dealer's service. total cost was under 1k, i had to do it couple months ago due to a bad EIS. You will need a "blue key" to reprogram the keys, and i am not sure you will be able to find it outside dealership.

Regards

Rudeney

SDS can read the code from the existing EIS and transfer it to the new EIS without the need for a green (or blue or orange) key from MBZ corporate. Most dealers won't do this because if the old EIS is defective, it's possible they won't be able to reliably read it. And if it has bad code that gets transferred to the new EIS, then the new one is toast. Once a new EIS is programmed it can't be "reprogrammed". Well, at least not by a delaer - it can be done with an EEPROM writer to wipe out its odometer reading thus making it "virgin" again.

Ghostty

Rudeney,

Completely agree. It can be done by a competent indy shop. But, considering that a USED EIS module + indy shop fee would be arround $400-500 any way, paying $900 for a dealer to do it with a NEW EIS module sounds like a good price for me

stykshooter

Well I've found someone who can repair EIS he also makes other repairs ECM ... etc as I'm kinda strapped for time & won't return to Texas til March, I may send

Rudeney

You can't code a used EIS anyhow (well, like I said, unless you reset the mileage stored in the EEPROM to zero with a 3rd party programmer tool ).A new EIS can be bought for under $500 (checc mboemparts.com) . Labor is maybe 3 hours tops. My dealer quoted $1500 for a new EIS installed, but they are crazy expensive on everything. $900 is a GREAT price for a dealer to install and program a new EIS.