I have a 1996 Jeep Grand Cherokee 4.0L which suddenly wont produce spark to start the engine. I purchased a mini OBDII bluetooth interface and paired it with my samsung note 4. I purchased the pro version of OBD Car Doctor because it gives progress of connecting. The interface has a red light on it when plugged in even with the ignition off. I turn the ignition to accessory or on and try to run the Car Doctor. It proceeds to run several test protocols and stalls on protocol 3. I can't retrieve any info from the ecu. How do I get past this? I am trying to determine if the ecu is working ok then wiring and any electronics that might be in the distributor.
I also tried a standalone innovis obd reader and it got a few monitor not run codes and it had a yellow light. According to their technical support their tools are designed not to show any codes until the monitors all have the status of being run. That is useless of course. I had disconnected the battery at one point since the car was running which would cause that. As a side note I have confirmed the coil is ok and there is 5 volt voltage going to something in the distributor (2 out of 3 wires) but can't find any voltage going to the coil yet.
