can't connect to EAS to clear fault

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Buzz1024

Member
Posts
63
Location
East Lothian
Have just replaced the battery and EAS not working - all lights on and the dreaded "35mph max" message up on dash :confused:
Easy I thought, just connect my Lynx which has proved invaluable so far, but all I get is a message about not being connected. I'm able to access everything else - BECM, engine ecu etc apart from the suspension.
I use a netbook with the Lynx as I can keep it all in the car so I've run antivirus etc on it to eliminate the netbook from the equation and it is all clean and working well.
My own thoughts are that I've got a duff fuse/relay somewhere (caused by changing the battery) that is preventing connection to the EAS but I'm a bit puzzled at the moment.
Has anyone had this problem and what am I searching for?
The laptop with Rave installed (and my Mercedes WIS software) has just has a hard disc failure so not having a good day - some beer may be in order later.
 
I've had a good look at the OBD connector and used some contact cleaner but no luck - the EAS was all working perfectly prior to the battery change - I had the Lynx connected 2 weeks ago and had comms to everything (teaching my 14yr old how it all worked)
I read somewhere about fuse 44 going and causing these symptoms but feeling lost without my Rave - having to use my tablet just now till I can get laptop sorted or replaced
 
Started pulling fuses etc but it's ****ing down now:mad:
I've had my planning permission passed for a 2 car workshop but having to work outside currently.
 
I've had a good look at the OBD connector and used some contact cleaner but no luck - the EAS was all working perfectly prior to the battery change - I had the Lynx connected 2 weeks ago and had comms to everything (teaching my 14yr old how it all worked)
I read somewhere about fuse 44 going and causing these symptoms but feeling lost without my Rave - having to use my tablet just now till I can get laptop sorted or replaced

Fuse 44 differs in it's use depending on year. Pre 99 it is the EAS delay relay 10 amp power. 99 on it is 30 amp and either powers the ECM (Petrol) or fuel heater (Diesel). Delay timer fuse on 99 on cars is 10 amp fuse 29.
 
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Mine is a 99 4.6HSE - its got the bosch fitted - it seems to be a bit of a changeover period vehicle with a mix of older and newer bits - I'll pop out when the rain stops and check if f44 is 10 or 30amp - where is f44, lost without my rave - incidentally, is there anywhere I can view rave online, I've searched but can only find where to download from
 
Mine is a 99 4.6HSE - its got the bosch fitted - it seems to be a bit of a changeover period vehicle with a mix of older and newer bits - I'll pop out when the rain stops and check if f44 is 10 or 30amp - where is f44, lost without my rave - incidentally, is there anywhere I can view rave online, I've searched but can only find where to download from

Doesn't it show in fuse box lid?
 
Mine is a 99 4.6HSE - its got the bosch fitted - it seems to be a bit of a changeover period vehicle with a mix of older and newer bits - I'll pop out when the rain stops and check if f44 is 10 or 30amp - where is f44, lost without my rave - incidentally, is there anywhere I can view rave online, I've searched but can only find where to download from

Both fuses 29 or 44 are in the engine compartment fuse box. They are numbered.
 
Thanks guys - I'll have a look when the fecking rain stops - I didn' t want to pore over the fuse box in the dark & rain - you know how p38s don't like the wet :)
 
try this-

we looked at mine the other day, other stuff would connect, eas was iffy

removed the trim piece that holds the socket, carefuly pop the socket out- give it a good BLOW a few times , like blowing dust ou the old snes/megadrive games (thats what gave me the idea haha) ,and just check/gently push the wires in

and try it out- it worked fine after that
 
I had a similar problem recently - couldn't communicate with the EAS ECU - after loads of checking, I narrowed it down to a faulty delay timer relay (it's a tall black one under the pass seat towards the door side, move the seat right back and you can reach it) not powering the ECU.

Quick and easy way to check this is replace it with one of the standard green 5 pin relays from the main fusebox.

Bingo! back in business - I didn't even have to plug the laptop in to clear faults.

Good luck.

Alastair
 
I ended up replacing the OBD socket, but not with one from the same year. I went to a local scrap yard, bought a couple of different ones from newer cars and made one up with the right pins for the P38. Connection was great from then on.

You could have damaged your OBD lead from the Lynx I suppose, but more likely to be the P38 OBD connector, especially if you have had blocked aircon drains and the water has been dripping through the OBD port!
 
the lynx is connecting to every other ecu in the car through the lead and existing obd socket - it's possible that there is some sort of damage but i'm thinking it's unlikely that the OBD socket is the cause of my troubles.
I'll start with the fuses and timer unit and see where things go from there - going to try and bail out of work early to try to do it with some daylight.
 
the lynx is connecting to every other ecu in the car through the lead and existing obd socket - it's possible that there is some sort of damage but i'm thinking it's unlikely that the OBD socket is the cause of my troubles.
I'll start with the fuses and timer unit and see where things go from there - going to try and bail out of work early to try to do it with some daylight.

All the systems have separate pin outs it is quite possible that pin 1, 11 or 12 that service the EAS are at fault. 1 is from delay relay 11 and 12 from EAS ECU.
 
Thanks wammers - I'll check the pins as well - I didn'tget a chance today, work kept me busy later than I planned but will try to get some time tomorrow
 
Have just been out and now have EAS working again.
I managed to get another OBD socket and EAS timer during the week but thought that rather than spend time upside down under the dash in the rain straight off I would work my way through - checked all the fuses first - all ok but no EAS nor diagnostic comms. Changed timer - still nothing, changed relay RL20 in main fuse box - success! I now have working EAS and full EAS comms restored.
So obviously RL20 can cause loss of comms to the EAS ECU if it goes - I can only assume that it was on its way out and battery problems have hastened its demise.
Definitely a happy bunny as it's now getting dark, windy & ****ing down - now inside having a beer.
Thanks for all your help.
 
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