[daspayth]

Hi All,

I'm new to the board so hopefully I'm posting in the right location.

I have a 2008 Ranger with about 100hrs on it. I had a friendly rat eat through 24 of the 25 main wiring harness wires. I attempted to repair the harness but ultimately I replaced the main harness as it would not start (no spark/no fuel pump at key on). I then suspected the ECU was toast so I replaced it with a aftermarket from Procomm. When I did it fired right up, however, the Procomm ECU does not support the rear solenoid (differential) so I ordered a OEM ECU. Well now I am back to the original problem (no spark/fuel pump). NOTE that everything ran using the aftermarket ECU. With the OEM ECU I get diagnostic errors 51/52 (Fuel Injection Open/Short) and occasionally error 25 (invalid shift position).

Since the aftermarket ECU works, I believe that the aftermarket is NOT looking for certain sensor response (just doesn’t look for it) which enables the engine start. Considering that it doesn’t with the OEM ECU (remember this is not the original – the original exhibited the same symptoms though). I am looking to see what things the ECU is looking for to enable the fuel pump and spark/ignition.

Any guidance appreciated

 

[Russ Chastain]

My first thought is that there are some other damaged wires somewhere, that may not be returning signals from those sensors. If a rat ate some wires that you have found, it mayhave gotten some other wires that you haven't found yet.

I would say to find and repair any such wires, then install the original ECU and give it a try.

 

[Slacker]

I know it sounds rigged. If you can't find the source of the problem you can control the rear solenoid with a separate circuit switch and relay. Again, horribly farmer, but if done with class a guy would never know what had changed.

I wish a I actually had a good answer for you but I don't know much about the problem you're having.

 

[daspayth]

Thanks for the suggestions; I thought about adding a separate circuit for the solenoid. However, it first fires 12 volts to actuat it and then just a "little" voltage to hold keep it in position. I don't know what a "little" voltage is (5v?). I'm good going with the farmer approach if I can't figure it out correctly. If you point me in a direction regarding this strategy I would appreciate it.

 

[Russ Chastain]

Thanks for the suggestions; I thought about adding a separate circuit for the solenoid. However, it first fires 12 volts to actuat it and then just a "little" voltage to hold keep it in position. I don't know what a "little" voltage is (5v?). I'm good going with the farmer approach if I can't figure it out correctly. If you point me in a direction regarding this strategy I would appreciate it.

JMO of course, but I would do my best to avoid that. It reduces the vehicle's usability and resale value, and there are probably other issues that may lead to major malfunction if you don't find and fix them.

Good luck no matter what.