Truck will not start.

[quote:ba2095925f="deadkins"]1900 Ford Ranger, 2.9 L, Automatic, 95000 Miles.
Truck will not start. No power to fuel pump, no power to ignition. Found no power was coming from the computer through the fuel pump relay, so I replaced the computer.
When I turn the key on, all the lights illuminate as normal on the dash. Engine cranks fine, fuel pump relay closes. No power through contacts of fuel pump relay and no ignition spark. Applied power to the terminal of the relay and the fuel pump will run, indcating the wires are okay from the relay back. Verified the "crash" switch under the right kick panel was not tripped.
Replaced, fuel pump, fuel pump fuse, computer, fuel pump relay. Vefied power at relay. (relay is closing) Verified fuel pressure (fuel pressure only when power is applied with a jumper @ relay). Replaced computer. All are present or okay.
My best guess now, is that power to the fuel pump and ignition is being stopped somewhere.
Additional information, alternator replaced 6 mo. ago. Both heads, timing chain and gear and distributor replaced 13 mo. ago.
Any advice you can add would be grately appreciated.[/quote:ba2095925f]




Check for battery power to the PCM that controls the memory at all times.

[quote:f4735b8d81="rasmataz"][quote:f4735b8d81="deadkins"]1900 Ford Ranger, 2.9 L, Automatic, 95000 Miles.
Truck will not start. No power to fuel pump, no power to ignition. Found no power was coming from the computer through the fuel pump relay, so I replaced the computer.
When I turn the key on, all the lights illuminate as normal on the dash. Engine cranks fine, fuel pump relay closes. No power through contacts of fuel pump relay and no ignition spark. Applied power to the terminal of the relay and the fuel pump will run, indcating the wires are okay from the relay back. Verified the "crash" switch under the right kick panel was not tripped.
Replaced, fuel pump, fuel pump fuse, computer, fuel pump relay. Vefied power at relay. (relay is closing) Verified fuel pressure (fuel pressure only when power is applied with a jumper @ relay). Replaced computer. All are present or okay.
My best guess now, is that power to the fuel pump and ignition is being stopped somewhere.
Additional information, alternator replaced 6 mo. ago. Both heads, timing chain and gear and distributor replaced 13 mo. ago.
Any advice you can add would be grately appreciated.[/quote:f4735b8d81]




Check for battery power to the PCM that controls the memory at all times.[/quote:f4735b8d81]

Would you have any idea wher it originates? A wire color? I have a Haynes Maunal, and most of the schematics are not accurate.
Thanks

Cannot recollect-its at the end of the connector-I think! its a white wire. Disconnect the battery,then unplug all the connectors from the computer, now connect battery find the white and stick a test lite to it.Also make sure the PCM/ECU is ground properly.

I'll be looking for that Info

[quote:c004c8f79d="deadkins"][quote:c004c8f79d="rasmataz"][quote:c004c8f79d="deadkins"]1900 Ford Ranger, 2.9 L, Automatic, 95000 Miles.
Truck will not start. No power to fuel pump, no power to ignition. Found no power was coming from the computer through the fuel pump relay, so I replaced the computer.
When I turn the key on, all the lights illuminate as normal on the dash. Engine cranks fine, fuel pump relay closes. No power through contacts of fuel pump relay and no ignition spark. Applied power to the terminal of the relay and the fuel pump will run, indcating the wires are okay from the relay back. Verified the "crash" switch under the right kick panel was not tripped.
Replaced, fuel pump, fuel pump fuse, computer, fuel pump relay. Vefied power at relay. (relay is closing) Verified fuel pressure (fuel pressure only when power is applied with a jumper @ relay). Replaced computer. All are present or okay.
My best guess now, is that power to the fuel pump and ignition is being stopped somewhere.
Additional information, alternator replaced 6 mo. ago. Both heads, timing chain and gear and distributor replaced 13 mo. ago.
Any advice you can add would be grately appreciated.[/quote:c004c8f79d]




Check for battery power to the PCM that controls the memory at all times.[/quote:c004c8f79d]

Would you have any idea wher it originates? A wire color? I have a Haynes Maunal, and most of the schematics are not accurate.
Thanks[/quote:c004c8f79d]


Fuse 19 in the central fuse box feeds the PCM diode coming from the ignition switch its red/light green wire. Also there's a black/yellow wire coming from the diode to the PCM relay.Then a red wire coming from the relay to the PCM. The red wire feeds pin#'s
71 and 97 on the PCM

HTH/Good LUck!
Rasmataz