What year is your truck?

 

Supposed to be a 96 according vin#. I bought it used. Transmission has been changed prior to me. There was some wiring issues when I went to smog it last year. Had to redo temp sensor. My guess is it isn't the original motor either but could be wrong. I'd have to research vin# again and match numbers with motor. 5.2l it's either a Y-code or T-code. Injectors at each runner. I'm still learning to an electrical issue but damn I've checked everything

 

Had to lookup diagram for PDC because cover on my PDC doesn't match.

 

Grab the service manual for your truck from here. I think it actually IS the 96 manual. That should be reasonably accurate.

 

Wasn't much help. Same PDC I have. No troubleshooting on the fuel system. But thanks. Pretty much knew all that information.

 

Was the PDC Changed out at some point? That's gonna make life REAL interesting....

The way the fuel pump circuit works is, PCM should ground the control circuit for the relay for three seconds at initial key on. Afterwards, it won't engage the relay until it sees the engine turning. (crank sensor signal) Can you determine which relay actually IS the fuel pump relay?

 

Yeah I'm going to take a shot here and say it's possible PDC is different. Just for the fact that the diagram on cover is different from what's in there. The picture in service manual is what I have plus I already had a printout of mine.

 

For some reason now I don't hear the relay click. Usually 2 of them click. I hear one. But now I'm not hearing pump prime. I've tried jumping everything in the relay box but nothing seems to turn pump on. The a/c clutch energizes for some reason with the fuel pump relay. The a/c clutch relay is supposed to be a smaller relay on the side bank of PDC.???? And like I mentioned when I pull the relay that's supposed to be for fuel system it won't turn over.

 

My other question is are all 5 pin relays the same. Like starter fuel and asd relays. Why do they say led lights relay or something else? They have all the same pins 30 87 87a 85 and 86. Part# EP27. And that's from all parts stores Napa included. The last one I got said flasher. Same part #

 

My other question is are all 5 pin relays the same. Like starter fuel and asd relays. Why do they say led lights relay or something else? They have all the same pins 30 87 87a 85 and 86.