EfiMini Diagnostic Board
Diagnostic Interface Adapter
This diagnostic adapter was and still is used extensively in any vehicle during the testing of the design phase. It serves the purpose of disconnecting all injector drive outputs from the efiMini and looping the injector drive signals from the ECU directly to the injectors. This still allows for the timing analysis of the injector signals, but without driving the injectors.
It's very inconvenient when you're driving and the cpu hangs during the testing of a new unreleased firmware and the vehicle looses its engine. So you flip a switch first, to get the efiMini into analysis mode, regardless of it's state, hung up or not ... then you have all the time in the world to reset the board or whatever needs to be done.
The same applies to the loop back option of the O2 sensors. If you do not get the correct response from the engine to your O2 out simulation profile ... it can be switched back to normal O2 sensor operation in analysis mode.
In simple words ... both switches in one position has the efiMini electrically connected between the ECU and the vehicle (injectors being driven by the efiMini and the ECU being provided with the narrow band O2 sensors simulated output voltages) ... both switches in the other position disconnects the efiMini outputs and reconnects the ECU to it's outputs like there is no efiMini present. The efiMini still measures the injector timing and the O2 sensor voltages.
While this all was and still is very important to the development team it is of less importance to the user. It is assumed that the efiMini does not crash and stall the engine this way.
For completeness we felt we wanted to also publish the in house developed tools used during the design and test of the efiMini.
The following pict shows a zoomed view of the efiMini diagnostic relay board.
It seems that the ref designators for C1 and Ds7 have been swapped accidentally :)
Followed by pics of the Relay board top view with the connection wires below.
Followed by pics of the Relay board bottom view with the connection wires below.
Diagnostic Interface Circuit
The following pict shows the diagnostic loop back relay circuits.
Note : All published design documentation is Copyright ⓒ efiLabs.com and its use is without exception FOR NON COMMERCIAL PURPOSE ONLY. For commercial licenses contact efilabs.com ... try us, we're reasonable :)