How do I bypass the solenoid to test the starter in a 1999 ford expedition?

Answer 1

Starter Feed Circuit Tests Disable ignition system. Connect volt/ampere tester to battery terminals. Refer to operating instructions provided with tester being used. Verify that all lights and accessories are Off and transmission shift selector is in Park for automatic transmissions or Neutral for manual transmissions, then set parking brake.Rotate and hold ignition switch in Start position. Observe tester. · If voltage reads above 9.6 volts and amperage draw reads above 250 amps, proceed to starter feed circuit resistance test. · If voltage reads 12.4 volts or greater and amperage reads 0-10 amps, proceed to starter control circuit test. · If starter motor turns engine freely at times, but starting system is still suspected, engage starter several times while observing tester. A starting system that has a problem should fail while performing this procedure.

After starting system problem have been corrected, verify battery state of charge, disconnect all testing equipment and connect distributor.

Starter Feed Circuit Resistance Test The following test will require a voltmeter accurate to 1/10 of a volt. Disable ignition system. With all wiring harness and components connected properly, perform the following: · Connect positive lead of voltmeter to battery negative post, and negative lead to battery negative cable clamp. Rotate and hold ignition switch in Start position. Observe voltmeter. If voltage is not detected, correct poor contact between cable clamp and post. · Connect positive lead of voltmeter to battery positive post, and negative lead to battery cable positive clamp. Rotate and hold ignition switch in Start position. Observe voltmeter. If voltage is not detected, correct poor contact between cable clamp and post. · Connect positive lead of voltmeter to battery negative terminal, and negative led to engine block near battery cable attaching point.

Rotate and hold ignition switch in Start position. If voltage reads above .2 volt, correct poor contact at ground cable attaching point. If reading is still above .2 volt, replace ground cable. Remove starter heat shield (if equipped), then perform the following: · Connect positive voltmeter lead to starter motor housing and negative lead to battery negative terminal. Rotate and hold ignition switch in Start position. If voltage reads above .2 volt, correct poor starter to engine ground. · Connect positive voltmeter lead to positive battery terminal and negative lead to battery cable terminal on starter solenoid. Rotate and hold ignition switch in Start position. If voltage reads above .2 volt, correct poor contact at battery cable to solenoid connection. If reading is still above .2 volt, replace positive battery cable.

If resistance tests detect no feed circuit failures, replace starter motor.

Starter Solenoid Test Connect heavy jumper wire on starter relay between battery and solenoid terminals. If engine cranks, perform starter relay test. If engine does not crank or solenoid chatters, check wiring and connectors from relay to starter for loose or corroded connections. Repeat test and, if engine still does not crank properly, repair or replace starter as necessary.

Starter Relay Test Place transmission in Park. Apply parking brake. Check for battery voltage between starter relay battery terminal and ground. Connect jumper wire on starter relay between battery and ignition terminals. If engine does not crank, connect a second jumper wire to starter relay between ground terminal and good ground and repeat test. If engine cranks in step 3, transmission linkage is misadjusted or neutral safety switch is defective. If engine does not crank in step 3, starter relay is defective.

Follow this step by step and you will pinpoint the problem.

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