CAN Bus error - single bar, engine cuts

[miker 9]

Ok, my 450 gurus.  Once again I have an interesting issue to deal with.  I think my little CDI has been waiting for me to retire to exhibit all of these issues, so at least it waited until I have the time to deal with it, right?

Anyway, lately while driving our 06 Smart 450 cdi has been just dying on us.  Three times at intersections while stopped or close to it, and once while going about 60 km/h.  While the single bar is on the dash it won't let us change gears, so we can't put it in neutral and push off to the side.  After a short rest it will let us start it back up again.  My first instinct is to look in the SAM unit, as I've had to re-wire a few wires around the harness in the past (fuel pump first, then the two lights beside it).  The last time was about 6 months ago, if I recall correctly.

 

Another possibly related symptom (and possibly not) is that for a few months the temperature readout in the dash has been about 7-10 degrees too high.

 

Any advice or hints from anyone who's been there, done that?

[Leadwing 565]

Single bar?? .... Usually, there are three bars and it could mean one of many different things.  Clutch actuator or reluctor rings are common culprits in causing these lines or bars.

[MikeT 747]

Something is not connecting in the CAN bus, so likely a wiring issue.  Could possibly be the SAM.

 

For the record: 

• single horizontal bar = CAN bus error
• three horizontal bars = shifting system fault

Very different issues.

[LooseLugNuts 557]

any codes set?

 

that might aim you in right direction for wiring issues

[miker 9]

2 hours ago, LooseLugNuts said:

any codes set?

 

that might aim you in right direction for wiring issues

12 hours ago, Leadwing said:

Single bar?? .... Usually, there are three bars and it could mean one of many different things.  Clutch actuator or reluctor rings are common culprits in causing these lines or bars.

No codes on odb2, single bar.  Indicates some kind of can bus error.

 

 

[LooseLugNuts 557]

obd2 reader wont read canbus problems

 

youll probably need a better scan tool or find someone with a star

 

or check as many wires and connectors as you can and you might get lucky....its most likely something in the actuator or trans wiring 

[miker 9]

I took out the SAM unit and cleaned all solder joints and connections with electrical contact cleaner.  While I did this I noticed two things that I also took care of.  FIrstly, some idiot (guess who?) used gorilla tape to keep the three bypass wires I'd installed to get around the burned harness for the right side lights and the fuel pump.  I replaced this with electrical tape after taking off the excess glue the gorilla tape had left on the pcb.  I also noticed that the red cap on the positive lead from the battery to the SAM had gotten itself lost somewhere along the way, so I rectified that as well.  After putting everything together, I noticed that hitting the brake before turning the key seemed to activate the instrument cluster.  I realized I'd put two connectors in the wrong spot (the add-on power on the side of the SAM).  I put them back and everything was ready to test.

 

I just got back from a 40+ km test drive.  Not only were there no unexpected losses of power, but the temp is reading a much more reasonable level.  It might be a degree or two high, but hard to say for sure.  Certainly not the 10+ degree high reading I'd been getting for a few months.  Here's hoping this is the end of it for a while.

[miker 9]

I've been a bit busy lately, but thought I'd update the topic.  The problems came back after about 200km.  I'm not sure why.  I'm going to try re-seating all connectors to the SAM to see if it's something simple.  Update: re-seating all connectors appeared to work, or maybe not.  I got a couple of 15km drives in to town and then back with everything good, then today on the way back from town it crapped out.  Insurance runs out next week and I'm snowbirding south for a bit.  I guess when I get back I better start looking at all of the wiring, possibly the ECU, engine ground strap, etc.

[stickman007 309]

CAN issues is communication errors between the different modules in the car - most likely between SAM and ECU, (but there are others that run on the same network ABS/TC, SRS, and Cluster). Check your CAN wires (high/low)...they should be a twisted pair that runs along the car to different modules (a parallel circuit with terminating resistors). Bet you there's a break in the wiring somewhere - its a harness issue, not modules.

[LooseLugNuts 557]

when i get stumped on something i usually run to youtube and run searches

 

my favourite teacher is a guy named Eric who runs his own small shop...the guy is great at electrical diagnosing....maybe try searching his channel for anything can/canbus and it will give direction ..i dont recall him ever working on a smart but i do remember him doing videos involving canbus errors

 

his channel is called South Main Auto LLC

 

 

 

Edited October 28, 2019 by LooseLugNuts

[bluezt61 1]

Hello all,  was the issue ever fixed?, I have the same issue on a 2006 Smart 450 Pulse.car starts fine then cuts out with single ba in the cluste. Will start on checking the connections to the modules on the CAN bus . Any help would be appreciated

[Willys 748]

Welcome to the site, have you run for codes yet, if not do so......
Next check all ground connections, near battery, and from engine to frame.....then start looking for all and any grounding pins on the body close to SAM/ZEE if that is what you have and ECU (which is on the underside of body central to the engine opening).
Yhese cars are notorious for bad grounds. IF your car has a SAM, take it out and open it up, it's easy just be careful. Look for a row of pins about 12 I think and check for bad solder joints. Do some research here and you'll find this a common issue.  It leads to the long thin plug on top of the unit I think it may be the N7 plug, but don't quote me on that number. It controls headlights, fuel pump,......to repair just remove old solder and resolder new joint using a hot soldering iron. There are many threads detailing this here.
Hope this helps.

 

I started life in Solihull many many decades ago.......good luck.

Edited June 13, 2020 by Willys

[bluezt61 1]

Thank you for the welcome and suggestions Willys,  This  vehicle was my daughters and she handed it back to me to fix when I had time..... 

No current codes from vehicle using Palmer PCMscan and an ELM 327 interface, this only talks to the engine ECU.  Some time back it did have an impending crank sensor code ( new crank sensor bought and will be fitted once this problem solved)

If there is ELM software that talks to the SAM and other modules on the SMART car could someone let me know and I will buy it as son has just bought himself a 2016 SMART.

When the single line and engine cut out occurred with a connection to the OBD, the communication to the ECU dropped whilst the ignition was still on..  

I have been checking and reseating the earths in the engine area as I have had the alternator off the vehicle for servicing (seized) and have had the single bar problem occur . I will check the connections to the ECU next .

The vehicle has a SAM and I will make the your suggested checks for the earths and then open up the SAM module and check the CAN bus connections and resolder if dubious ..

I have the pin outs for the ECU and the SAM from being with Evilution in the past.

 

p.s I know Solihull (spiritual home of Land Rover) very well and live in Sutton Coldfield near to the Jaguar plant., all ok here, hope the same in Canada. 

.  

[Willys 748]

When you played with your alternator, I hope you disconnected the battery.....obvious but some miss it. You could short the main power lead to the battery causing serious damage maybe? The STAR system is the only system I know of that talks to the entire vehicle to solve the most nasty issues. Search out threads on how to buy a used one here, we talked loosely about where to get a grey version which work , slow but work.  Not cheap if you try and use modern laptop instead of the old Dell 640 I think it is. They are getting like chicken lips, a bit hard to find any where...lol.  I would install that crank sensor first as it may be all your issues...?  Not easy in the car but if you lower the engine sub frame and remove half the rear of the car easier, so I have been told. I did mine when whole engine etc was out while rebuilding. I also cooked my first ECU whilst trying to clean the plugs using sensor cleaner and a tooth brush, seems there is enough juice stored inside it to jump pins and fry board, so beware!!!!    Then you'll require said STAR system to teach the new to you ECU to speak with the other 2 computers.  IF you do try to buy a STAR as Stickman007 here if the newer Smarts work using the M3 multiplexer or if you need to buy a more modern version, which are available. For some reason it's the M3 that is recommended for the older Smarts...?   I'd be going after all 3 of my computers and crank sensor to look for corrosion, damages to strike each unit out of the issue at hand. All you can really do without the STAR is look for the obvious and repair any damages not be able to teach each one. 

Good luck.....I'm not sure either if you have the European version of the SAM or not and if so, from what people say it's not as bad for issues, but do not quote me on that....lol

 

[gtjunk 12]

9 hours ago, bluezt61 said:

Thank you for the welcome and suggestions Willys,  This  vehicle was my daughters and she handed it back to me to fix when I had time..... 

No current codes from vehicle using Palmer PCMscan and an ELM 327 interface, this only talks to the engine ECU.  Some time back it did have an impending crank sensor code ( new crank sensor bought and will be fitted once this problem solved)

If there is ELM software that talks to the SAM and other modules on the SMART car could someone let me know and I will buy it as son has just bought himself a 2016 SMART.

When the single line and engine cut out occurred with a connection to the OBD, the communication to the ECU dropped whilst the ignition was still on..  

I have been checking and reseating the earths in the engine area as I have had the alternator off the vehicle for servicing (seized) and have had the single bar problem occur . I will check the connections to the ECU next .

The vehicle has a SAM and I will make the your suggested checks for the earths and then open up the SAM module and check the CAN bus connections and resolder if dubious ..

I have the pin outs for the ECU and the SAM from being with Evilution in the past.

 

p.s I know Solihull (spiritual home of Land Rover) very well and live in Sutton Coldfield near to the Jaguar plant., all ok here, hope the same in Canada.

.  

 

I have not used it myself, but I have read on SCoA that Torque on Android (perhaps other platforms?) can pull can bus information with the ELM chipset.

I use an iCarsoft MB v2.0 which works on my 451 and claims to support the 450 (but untested by me)

Edited June 19, 2020 by gtjunk