A1996 FJ80 question. Does anyone know what the cut-out relay is for? It is wired between the ignition and the fuel pump relay. It has a circuit that must be grounded for the relay to close and the fuel pump to operate. The computer supplies the ground for it to operate normally. My question is what could cause the computer to shut of the ground to this relay thereby cutting off the power to the fuel relay. I have not seen anything in the manual. I would guess that it could be used by the computer to shut the engine off for a number of reasons. I have not been able to find any explanations in the factory manual.
Let me be the first to say please give us some more info,
primarily what year is your truck and what is the exact problem, might be of a little more help then.
Dave
1996 FJ80. The problem is as stated above. The computer no longer is grounding the cut-out relay circuit. It may be a bad computer, but I would be nice to know the purpose of the circuit. The relay is currently bypassed. The truck is up and running fine with no trouble codes.
Do you have the alarm unit or an alarm unit in your truck??
just curious if this is a possible culprit, check out beowulfs site for schematics of the rs 3000 system.
just a stab in the dark here.
Dave
The 80 had the alarm disconected and the Uni chip for the turbo disconnected in the process of isolating the problem. I think the air bag deployment makes sense. What we were looking for was if anyone knows for sure what deactivates this cicuit thereby cutting off power to the fuel pump.. Thanks!
The 80 had the alarm disconected and the Uni chip for the turbo disconnected in the process of isolating the problem. I think the air bag deployment makes sense. What we were looking for was if anyone knows for sure what deactivates this cicuit thereby cutting off power to the fuel pump.. Thanks!
I think that you would be way better off without that UniChip; I definitely do not use my unichip per the advice of many trusted mechanics. The stock computer is completely capable of running the turbo reliably. The UniChip has a reputation of unreliability and apparently around here has stranded several people. Problems I've heard about are assorted fuel problems, spark problems and flat out failure of the chip. Another problem is right after or at installation of the chip, the cruiser should be tuned on a four wheel dyno; failure to do this, according to APS is inviting performance problems. Along with the reliability worry, the fact that the UniChip would have probably prevented me from doing my own tune ups forever into the future, means that even if it was equally reliable, I probably would not want it. I am not sure how simply the chip can be removed but if it is simple, and if you're asking my opinion, my opinion would be to take that thing off your rig's computer. HTH
