the lorry is a 2003 815, first off. i have a red warning light on the instrument panel with TCO. This light comes on and off along with another fault which is ABS WITH AN AMBER LIGHT, usually for around 10secs each
i have booked the lorry in to have the tachogtaph get its 2 year inspection however the man said the inspection would not put out the reg TCO light. Does anyone know what this is and how to get it out.
today when i turned the ignition off it beeped and came up with an exclamation mark?? the tacho still scribes and marks charts as it should
the make is a stoneridge veider root analogue type.
I AM ALSO HAVING ABS PROBLEMS! the light doesnt seem to want to go out. We had it plugged in and got the following codes after replacing the front right ABS SENSOR AND EXCITIER/ ABS RING.
FRONT ABS SOLENOID VALVE (MEM)
FRONT RIGHT POLE WHEEL (ATT) I WAS TOLD THAT ONCE THIS IS RECTIFIED THAT IT WILL CANCEL THE OTHER 2 ?
FRONT RIGHT REV SENSOR (MEM)
THE GUY TOLD ME THAT THE CODE IN THE MIDDLE WAS AN AIR GAP ISSUE OR DIRT ON THE SENOSR OR RING?
I HAVE CHECK THESE HOWVER THE SENSOR XCAN BE MOVED WITH YOUR HAND… SHOULD IT BE TIGHT IN THE HOLD ON THE HUB??
ANY HELP AT ALL WOULD BE MUCH APPRECIATED. I HAVE SPENT LOTS OF TIME AND MONEY ON THIS AND AM NO FURTHER FORWARD!
firstly, turn your caps lock off, there’s a good boy
secondly, the TCO is a tacho fault, will need to be inspected by a tacho technician, it could be something as simple as the tacho disc is not correctly inserted
as for the ABS faults that you mentioned, those that say (mem) are memory faults, previous faults that are just stored in the memory, if you get the memory wiped, it should clear these
the one marked (att) is an active fault, hence the light keeps coming on, if your fitter says it is an air gap issue, then remove the sensor from the hub, clean the end of the sensor and refit it, getting it as tight up to the exciter ring as possible, almost touching
whilst you have removed the sensor, get a good air line and clean out the exciter ring all the way round, dirt and brake dust clogs it up so that the sensor can’t read it
livefreeordie999:
the lorry is a 2003 815, first off. i have a red warning light on the instrument panel with TCO. This light comes on and off along with another fault which is ABS WITH AN AMBER LIGHT, usually for around 10secs each
i have booked the lorry in to have the tachogtaph get its 2 year inspection however the man said the inspection would not put out the reg TCO light. Does anyone know what this is and how to get it out.
today when i turned the ignition off it beeped and came up with an exclamation mark?? the tacho still scribes and marks charts as it should
the make is a stoneridge veider root analogue type.
I have had this light show up in the past and have had no problem with tracing. It ended up being a pulse from the unit identifying that it was due for it 6yr cal . Aside from that it will be a fault that would need to be dealt with by your local Tacho engineer/workshop.
I don’t wish to worry you unduly, but one of our customers has a 52 reg 1218 that had the TCO light on all the time, then the fuel guage went off, we had a ‘spark’ check it out & he said “dash board”!!
We sent it to Merc’ & they said “dash board”!! So, we ordered a new one for the customer and the fuel guage now works perfectly, but, the TCO light stays on as if there’s no disc etc. When Merc tested it they had it in their tacho bay and they recon that there’s nowt wrong with it, but nobody can explain why the stupid light is constantly on, good eh■■?
I thought electronic ‘diagnostics’ was going to make this a thing of the past!!
If your TCO light is illuminated in a Merc than the parameters in your Stoneridge Tachograph are probably set incorrectly. The Mercedes Atego electronics are excellent,but the problems seem to occur when technicians misinterpret them/or are not really sure what they are doing. The Stoneridge unit is far superior to the Siemens VDO unit and gives far less grief in service. When a fault occurs,canbus displays it on the dash and keeps it there until your tachograph issue has been cleared.
Take your truck to a good Stoneridge technician who is familiar with both the Mercedes and the Stoneridge products. The Mercedes electronics will also alert you when a calibration/two yearly check is due. If the calibrating technician does not reset the tachograph head unit properly,then it will keep the warning light illuminated. Make sure the ‘Reset Heartbeat’ parameter is switched on.
When you are checking your tachograph…ensure you have two charts inserted correctly and put both duty mode knobs to the rest position.
In our experience,the Stoneridge unit very rarely gives trouble…it is normally the sender unit or a cracked wire tends to be the issue
Thanks for the advice, i got the tacho 2year inspected and think i have solved
That problem. However now and again whilst im driving the tco light flashed up with an amber light.
Should i insert 2discs? I am the only driver
Of the lorry though.
As for the ABS problem. Still no luck and now i have changed the whole hub with a new ring aswell.
Still no luck! Still lights up amber
My mechanic doesnt know what it could be but said if it was him he would change the ABS pump??
Would this be related to the solenoid valve or the same thing?
This is costing me a fortune, and im guessing if vosa pull me they will put me off the road because of it?
At a recent VOSA check at Scotch Corner I got a 7 day delayed Prohibition for the same fault on my Atego.
Put it on Diagnostics at Mercedes, found NSF sensor was faulty. Replaced it then had a partial retest including a full brake test. Its in your best interest to try and sort it as VOSA don’t see it as a minor fault. Have you had it in at a Merc dealers for a proper check? Hope you resolve it soon,jobs hard enough as it is without time consuming niggles.
Good news! At last, we replaced the abs pump and it took the light off. My mechanic said the dignostics machine only really points you to the correct side where there is a fault. He also said that you should hear a “click” when you turn the ignition on. ( this is how you know your abs pump is working on the atego).
One more question though. The only light on the dash now is when i put the lights o . An amber warning light illuminates with the bulb symbol. However all my lights are working fine. Anyone any ideas? Wrong wattage of bulb maybe?
livefreeordie999:
One more question though. The only light on the dash now is when i put the lights o . An amber warning light illuminates with the bulb symbol. However all my lights are working fine. Anyone any ideas? Wrong wattage of bulb maybe?
Probably the cause, but worth following Shuttles advice first
Merc fit 10 watt bulbs in the tail lights as opposed to the usual 5 watt, and earlier Mercs are more sensitive if they’re replaced with the lower wattage. Various ways round it, buy 10 watt bulbs from Merc get the merc dealer to re calibrate the diagnostics just so you can use 5 watts or just wire an extra marker into the circuit
I stopped worrying about warning lights on the Atego. Only the water temp buzzer. I went ALL over Europe in them and the lights were flashing all over the shop…As another poster said…“BLACK TAPE!”
And as others have said; deliberately hiding faults will not go down well when you are stopped by VOSA. I know they are annoying but they are there for a reason.
. Aside from that it will be a fault that would need to be dealt with by your local Tacho engineer/workshop.
get the merc dealer to re calibrate the diagnostics just so you can use 5 watts 
or just wire an extra marker into the circuit 