99 c70 going to figure out starting without chip key

Post by **corviarbob** » 23 Nov 2015, 16:02

so sunday i took the ign. switch out of the car 99 c70 vert. and took the key i made and got it to turn the so the switch turned. i put the real key on the ign and tried it and it started every time. this week i will get 2 more keys made for just opening the doors and tape the chip inside on the ign and then i have the keys back. i think i have found a way to bypass the permission box. i will work on that this week and if it works i will post how i did it for those that may want to get past that. i found the wiring. the box has half dozen wires and one gets power from the key and then after it gives permission send it to the ecu. i may be able to get past that. if not the stand my of the key taped to the ign. switch will then work. i have a few cars like that now. yea it bypasses the security but then you have to know what car in the lot has it. i found a local locksmith and he said he charges 30.00 per key to make the door keys. of course he said it will not run the car but then all i need is to get in the car to get my keys. so 60.00 is way cheaper than my local smith, he wanted the car there and would not guaranty it would even turn the ign switch for 25.00

Post by **Ozark Lee** » 23 Nov 2015, 23:05

The lines from the immobilizer and the ECU are data lines, not on/off toggle lines. The ECU asks the immobilizer a question and then checks the answer against its internal programming. It is a data stream rather than a discreet high or low signal. The only way I know of to defeat the process is to re-flash the ECU with new code to get the ECU to never ask the question nor expect an answer. I think some have tried but they run into checksum errors when it gets rewritten.

The ME7 is a pain for shadetree mechanics.

...Lee

matt122s · Post by **matt122s** » 25 Nov 2015, 18:05

At the Volvo dealership I worked at if a customer wanted remote start installed on their car we would have to bury a programmed key in the dash close enough to the antenna that reads the ignition key. It was the only way to get the car to start when the key's not in the ignition.
Bob it sounds like that's what you're doing with one programmed key tapped somewhere in there and then just a cut un-programmed key for the door that also turns the ignition.
If I had a newer Volvo with a chipped key I would do the same thing, I don't think Volvo's are high on the hit list of stolen cars.