Seat Arosa 2002 1.0 AUC Bosch Motronic ME 7.5.10 Non Start - No communication with ECU #Archived Message
Posted by David Jackson on June 29, 2007, 11:54 pm
Really struggling here had about 30 hours on it and got no where, hope one of you guys can help. car has come from another garage story is that lady was driving car home and a light came on dash (don't know which light) she got home tried to start car in morning battery was flat other garage went out fitted new battery still won't start they towed it in fitted new intermotor coil and Bosch ignition module still wont start. Car then dropped at my door ;-( When ignition is turned on there is no MIL light, fuel pump does not prime, pump relay does not switch in. I can't get any fault codes because no diagnostic machines will communicate with Engine ECM, but i can communicate with immo, instrument,srs. There are no fault codes stored in any other systems. Have no spark, no fuel. I have followed pin data from Autodata earth to ecu pins 2 and 28 test OK. live feed to ecu pin 15 Bat+ is ok at 13v and Pin 27 ecu from ign switch is ok 13v ign on.
All 5v ECU outputs are missing, pins 6,8,55,62,68,70,75 are all at zero with ign on. Also fuses 1,3 and 40 in fuse box above pedals are dead these seem to be fed from fuel pump relay. Fuel pump relay does not look the same as shown in any Autodata diagrams, my system seems to have two relays one of them being a double relay. The relay numbers are 405 and 167 going off autodata there is no 167 and 405 is for a diesel, i called the dealers and both relays are listed for fuel pump. i tested relay 167 it is OK, but 405 is a 6 pin electronic relay with a pcb and ic inside and i could not work out how to test it so i ordered a new one but it made no difference. I am missing the coil earth for relay 167 pin 86 on my relay this is fed from pin 26 ECU,ecu switched earth. If i give pin 26 on ecu an earth my relay 167 works and fuses 1,3 and 40 go live and the fuel pump runs but no spark and no start and still no coms with ecu. I suspected an ECU problem so i sent the ECU to ATP electronics via my local agent Camco. The ECU was returned a few days later ATP said it passed all tests and no sign of claimed fault. I then suspected immobiliser although i have no fault codes. I have tried to re match the keys to the immo but after entering the 4 digit security code the programming will not go any further. I then called my local lock guy out who uses the AD100 he checked immo unit for any codes all ok no faults, he then tried to match the keys in with his tool but that also froze up at the same point. My lock guy said these are one of the easiest immo units to program and are interchangeable if you have the 4 digit codes for any old units. He Carry's a spare so we tried to program the spare unit but this did exactly the same froze the machine at the same point. My lock guy also said that he did not think it was an immo fault because they always put the light on or at least the car starts for a second or two, this car does not do either. Any help and suggestions much appreciated and a correct wiring diagram would be much appreciated.