freegdr

check for power on no2 in pdc box under hood...look here...http://www.naxja.org/forum/showpost....26&postcount=4

Sir Jeep-a-Lot

Ok will do...I replaced the pump bc I had almost fixed all of the stalling & sputtering issues, except I could tell the pump was going bad as well. For the 2 drives I made with the new pump, it drove perfect with no issues at all.

ET JEEP

Check your fuses. The fuel pump relay should get constant battery voltage at pin 30, regardless whether key is on or off. You should read battery voltage at pin 30. When you turn the key to start, the ECM grounds the trigger circuit on the relay, thus activating the relay which then sends battery voltage to the fuel pump via pin 87 on the relay.

By what you describe, it appears you do not have battery voltage to the relay. It should be the same on the automatic shutdown relay.

Sir Jeep-a-Lot

There's no power at anything in the PDC...I did find the 30A "engine control" fuse to be blown, so replaced that.

Sir Jeep-a-Lot

Yeah, so if there's no power at the PDC, it must be the battery right? Because there's nothing else in between the PDC and the battery...I didn't think it could be the battery because the dash lights come on and the dash gauge shows between 10-12volts. And I thought if a battery was dying, it could usually still be jumpstarted?

Could it be the battery water level, or that the battery has enough power to turn the dash lights on but not enough to power anything else? Think I'm gonna get a new battery today, because I have no idea how old it is...

sthon

Does it crank over?

Sir Jeep-a-Lot

The starter clicks when I turn the key and I can hear it spinning, but no start...fuel pump doesn't come on.

sthon

Have you checked all your grounds yet?

Sir Jeep-a-Lot

No I haven't, good call. Which specific ones should I check?

ET JEEP

So the problem is a bit more than no fuel pump. Take your battery to an auto shop and have them load test the battery. You need to start with a good battery and a charged battery. Also the positive and negative cables have to be in good order and the terminals need to be clean and tight at the battery, positive n negative, ground on engine and clean n tight at starter connection.

Follow the battery positive cable and there should be a connection to the PDC. You may have a problem in this area as you do not have power going to the PDC.

Starter clicking could be a starter, starter solenoid, battery or battery cable problem. You need to start with the above listed steps.

Sir Jeep-a-Lot

OK so I just put in a new Interstate Mega-Tron Plus battery, and now there is at least power at the PDC. I also cleaned with baking soda and a toothbrush. Fuel pump still doesn't come on...

The other day I noticed the 30A fuse 2nd from the right I think at the F9 spot (labeled something like 'engine control' on the lid of the PDC, but labeled 'PCM' in the FSM) was blown. I replaced it, but then when I hooked up the new battery it blew again ($5 fuse...doh!). My test light shows power at both terminals of all the fuses except for the one that blew...only shows power at one terminal for that one.

Any ideas why this fuse would keep blowing, and would it be related to the fuel pump not turning on? Also, how would I be able to tell if a relay is bad?

freegdr

good chance that stopping current from getting to pump

freegdr

pull fuel pump relay see if fuse still blows...

freegdr

shows f6 powering fuel pump relay here...http://www.jeep4x4center.com/jeep-se....swf#toolbar=0

ET JEEP

I don't have a detailed wiring diagram for you vehicle. From what you write and what I have, it appears that the fuse that blew powers the PCM, automatic shutdown relay and the fuel pump relay.

Do this test. With fuse out, since it is blown, test for voltage at pin 30 of the automatic shutdown relay and the fuel pump relay. There should be no voltage if this is the fuse that powers those items.

If you get no voltage, do a continuity test between the dead terminal at the fuse and pins 30 on both relays. You should have continuity. This will identify the fuse as the engine control.

Since you changed out the fuel pump and started having the problem, I would go back over the work done to make sure it is correct and not causing the problem. You may have a short in the fuel pump wiring.

You can test a relay with a 9 volt battery. Do a continuity test between pins 86 and 85. You should have continuity. No continuity=bad relay. Do a continuity test between pins 30 and 87. There should not be any continuity.

Now apply positive voltage to pin 86 and negative to 85. This activates the relay. Now do a continuity test between 30 and 87. You should have continuity. Relay is good. No continuity= bad relay.