Afternoon All,
I have a manual swapped L701 Cuore, it has a transmission from an EJ-DE Sirion. The car is still using the auto L38 Denso ECU and has the auto gear selector switch still connected and set to neutral, so the ECU still allows the car to start. I have found a manual M20 Denso ECU off an M100 EJ-DE Sirion and tried simply plugging it in and starting but this didn’t work. The car cranks and starts for a second then dies. I have checked the pins/ pinout and am pretty sure they match, I suspect maybe this is caused by the immobiliser? I don’t have the key or key barrel from the ECU donor car, if this is an immobiliser issue is there a way to bypass the immobiliser? Are there any other things I should try before attempting to bypass the immobiliser?
Any help or information about these ECU’s and their compatibility would be very appreciated.
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Yes almost certainly the immobiliser with those symptoms I’m afraid.
As far as I am aware, these ECUs are ‘locked’ preventing fiddling around like you can with VW PD engine ECUs for example. However, it might be possible for an automotive electrician to bypass the immobiliser sensor on the steering column.
I think that the ECU needs an ‘OK’ signal from the immobiliser sensor which is essentially and RFID sensor mounted near to the key barrel, it senses the static code in the immobiliser chip on the key and then sends a signal that the code matches the expected value in the ECU.
I’m not sure if you can ‘read’ the immobiliser code that the ECU is expecting and the recode the key to have that code, or do it the other way around so you read the code in the key, then update the value that the ECU stores so that they match.
I suspect coding it out entirely will be a very difficult task.
The other option is that if you can get a key that is already married with the ECU you have (or a new ECU + matching key) then you can just tape the matching key to the inside of the steering column shroud so that when you start your car with your normal key, the immobiliser chip RFID sensor will detect the taped-on key code instead and let the car start and run.
I’m not sure if that helps or not, I understand the principles but I am afraid that the electrical side of things is beyond me. What I can tell you is that the OBD system on these cars is very simple but also locked - I have access to a £10k OBD scanner tool which can do a lot of CANBUS coding on many cars, but the options for Daihatsu is very limited, mostly just reading of individual sensor values and reading and clearing engine management fault codes. You can’t get anywhere near as ‘hands on’ with a Dai ECU as you can with a VW PD one for example.
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I think Granger is pretty spot on with all this the other easier way is to try to soruce an early sirion ecu that does not have the immobiliser set up. They are the same metal style casing as the L7 one you have pictured. It may be more difficult to find but it they work. May I ask why your concerned about getting the manual ecu over just using the auto one?
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