lord morpheus question:

relay position 87 has no volts. 30 is 12.3v 86 is 12.3v and 85 is 5.6v

on the relay itself these are labeled respectively #5, #3, #1 and #2


Here is a rough sketch of how the terminals look
_
I _ -

far left is #5/87 and has no volts
Far right is #3/30 12.3v
center upper is #2/85 with 5.6v
center lower is #1/86 with 12.3 v

only stored code was p1230 fuel pump relay open circuit. let me go see if the alarm light is on

there is no alarm light on or flashing. I think I see it, LED bulb in the middle of the gauge cluster near the bottom. On light on is Service Engine Soon which stays on constantly. This EKA code where would I find the EKA for this truck? Is that something the dealer could give me if I gave them the VIN? When I bought this truck they didn't have a remote entry key for it. Only 1 standard metal hardware store key. Obviously no computer chip or radio signal being emitted there. Could that be part of my problem?

Also I have noticed that while messing with the interia switch plug, taking it on and off again, the 4 way flashers would come on randomly. I couldn't get them to go off without disconnecting the ground cable on the battery for a few minutes or so. I thought this had to do with the inertia switch, is it possible that is part of the reason it won't supply 12v to the fuel pump ?

87 has 0 volts because it goes to pump, and no voltage is going to pump.

30 has + volts from fuse. If you jump 30 to 87, pump runs. Don't do this for more than a few seconds.

86 and 85 both have volts because ECM has not "grounded" the lead going to the relay coil. If relay was plugged in, and you were able to read across 86 to 85 you would not see 11-12 volts needed to operate relay. If you plug in the relay, it probably does not click. So ECU is holding it off.

When you turn the key (not all the way to start) you should have Main relay (controlled by inertia switch and ECU) come on. You should also have fuel pump relay energize for a few seconds. Do both of these relays come on? The main relay MUST be on for the fuel pump realy to activate if ECU wants to make it run.

With key "on" but not in "crank" position, unplug inertia switch and plug back in You should hear main relay click. What happens when you do it?

Have you turned on truck, not to crank, just to run, and let it sit that way for 5 - 10 minutes? This may allow ECU to start talking to BCU again.

At one point I was thinking main relay, but if the main relay weren't energising, the starter relay would remain open.

With key on but not crank, I disconnect the interia switch and immediately the 4ways start flashing. They will not go off by removing key, or cycling the 4 way flasher switch. Only way I can find to get them to quit is pull the ground wire of the battery for a few seconds. I am going to try to leave key on for 10 min now and see what happens