stamp11127
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In the battery junction box, mini fuse 10 is hot at all times. This protects the secondary side of the fuel pump relay(fpr) which runs the fuel pump. You should have 12v here.
The secondary side of the fpr has two blades were interested in, #30 (pwr feed) and #87 (pwr out). You should have 12v at the connector that #30 plugs into. Most relays have the numbers on the bottom of them next to the blade for you to tell which is which.
With the inertia switch unplugged, remove the fpr, jump #30 to #87(where it plugs in) you should have 12v at the inertia switch plug. If it is less than 12v check the voltage at the top large connector of the three large connectors on the driver side firewall next to the brake booster. This is the only connector between the fpr and the inertia switch connector.
All of this is testing voltage on the DG/YE wire.
If you have 12v at the inertia switch connector the next step is up to you. You can jump the inertia switch by jumping the DG/YE wire to the PK/BK wire. You now are supplying power directly to the fuel pump & can try starting. Pull any of the jumpers to kill the fuel pump.
If you drop down to the 6.8v anywhere on that wire you have a bad connection or high resistance causing the voltage drop.
Since you can run a dvm I'm assuming you know how to make the jumpers. If not I'll give you some step by step instructions, just let me know.
This is from the wiring diagram for a 99. Hopefully they haven't changed anything if yours is a different year.
The secondary side of the fpr has two blades were interested in, #30 (pwr feed) and #87 (pwr out). You should have 12v at the connector that #30 plugs into. Most relays have the numbers on the bottom of them next to the blade for you to tell which is which.
With the inertia switch unplugged, remove the fpr, jump #30 to #87(where it plugs in) you should have 12v at the inertia switch plug. If it is less than 12v check the voltage at the top large connector of the three large connectors on the driver side firewall next to the brake booster. This is the only connector between the fpr and the inertia switch connector.
All of this is testing voltage on the DG/YE wire.
If you have 12v at the inertia switch connector the next step is up to you. You can jump the inertia switch by jumping the DG/YE wire to the PK/BK wire. You now are supplying power directly to the fuel pump & can try starting. Pull any of the jumpers to kill the fuel pump.
If you drop down to the 6.8v anywhere on that wire you have a bad connection or high resistance causing the voltage drop.
Since you can run a dvm I'm assuming you know how to make the jumpers. If not I'll give you some step by step instructions, just let me know.
This is from the wiring diagram for a 99. Hopefully they haven't changed anything if yours is a different year.
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