yo germanflames,
Battery Voltage is too low; have it charged and tested.
Voltage; "...a normal battery that is fully charged produces 12.6 volts, not just 12.0 V. (Remember, when measuring battery voltage, everything in the car should be off, or the battery should be disconnected. Voltage measurements are always "no load" measurements unless the battery is being tested for it's performance under load)..."
Source: by Gordon via miesk5
"...Because many of the new alternators are capable of charging at rates in excess of 110 Amps, the battery should be fully charged before use to avoid overheating the alternator by trying to use it as a battery charger. Alternators are NOT battery chargers, they are battery maintainers as well as supplying current for vehicle amenities. Symptoms of this type of damage are a burnt stator. In many newer vehicles, the alternator is located in an area that allows very little ventilation. The area around the rectifier on the back of the alternator plugs up with dirt and fibers, causing the unit to overheat. Rear alternator bearing failure may be caused by over tightening the belt or a seized belt tensioner. The bearing is retained in the alternator by either an aluminum ring or a plastic retainer, which under pressure, will collapse. Drive belt slippage may cause overheating and bearing damage. Thread damage on the rotor of the alternator is caused by improper pulley installation methods. Cracked terminal insulators are cuased by over tightening the terminal nuts. Improper changing of the alternator clock postion may result in broken brushes and brush holders..."
Source: by thirskauto.net via web.archive.org
No Crank Condition; with key off; turn headlight on; are they ON? Does Horn work (assuming it has worked recently)? Check Alternator Belt &the tensioner; Headlights are white and bright --- This means the battery has 12 volts or so but it does not tell us if the battery is capable of
providing the amps necessary to turn the starter over. First quickly touch each battery cable connection at the battery. If either one is warm to the touch, that indicates a bad connection. Wiggle, push and pull the battery cables back and forth and see if the headlights come on white and bright. If the headlights come back on and as you hold the cable to one side or another, have someone try and start the car. More than likely, it will start. Work towards white and bright headlights first. Even if you can't get the headlights to shine white and bright by wiggling the cables or ends, then you might next try to jump start your dead battery.If the starter is bad and you hit it with a hammer a couple of times..."
Source: by Mark S at Salem Boys
No Crank in a 92-96; Internal Relay Terminal (contact) Corrosion; Starter Wiring Diagram in a 96; from Ignition Switch to Starter; Note that Ford often confuses us by labelling the Manual Lever Position as a "Transmission Range (TR) Sensor; or as Steve describes below as the neutral switch. the starter works as it did when you bridged the relay's Large Posts, but doesn't work using the key, bridge from the rear post (the one with the LARGER cable) to the small (S) post. If the starter works, the relay is good and the fault is between the ignition switch & the relay (clutch switch or MLPS (in automatic tranny (E4OD)). If not, the fault is at the relay. If the
relay didn't
click, either it's not grounded (check to see if it is secure to inner fender or there is rust or grime between inner fender and relay body), or its coil is burned out. If it did Click, its contacts are corroded/broken.
The relay trigger wire (R/LB) comes from the ignition switch via the clutch switch or MLPS and should only be hot with the key in START and either the clutch fully depressed, OR the auto shifter in P or N. check is wiring. Between the large posts of your starter relayshould be a smaller post with a wire attached. This is the wire from your ignition switch through the MLPS, Or clutch safety switch on a manual trans to the starter relay and the on to the starter solenoid and starter. Check this wire for cracks, open insulation, or anything that could possibly cause an open circuit. check your upper ignition actuator. Find the ignition rod (on top of the column, running from the steering wheel down to the ignition switch at the base of the column) and make sure it's moving back and forth when you turn the key, through all positions. If it is, your upper actuator is probably not the problem.check your ignition switch (again, at the base of the column). Manually push the switch back and forth through the different positions. Push it all the way forward (or down) and see if it will engage the starter. If it does, then your ignition rod is probably bent, which can be remedied quite easily. & If it's an auto, try starting in neutral or while pulling up on the lever while it's in park. If that works, look to the MLPS. You could try jumping from hot to the small terminal on the starter relay to test it's operation. Sometimes new ones are bad out of the box. If it won't turn over when jumped to the small terminal, you'll know that it's a starter relay issue (Bad part, bad ground). If it does turns over jumped to the small terminal, then you'll be looking for something in the small circuit that includes the ignition switch & the MLPS Or clutch safety switch. There should be 12v running from the ignition switch, thru the MLPS, to the small terminal on the starter relay. Disconnect the small wire to the starter relay (So it doesn't start by surprise, I'd pull the coil wire too). With someone holding the key in the start position, you should be able to read 12v between any point on that small circuit & ground. When you find where you lose 12v, then you'll know where the issue is; , see Starter (@) Relay Jumping Image in 92-96, Sewiw shows a remote start switch's Jumpers; you can use a small jumper
"...Why are the cables and battery so important? The starter circuit pulls a lot of amperage, up to 500 amps depending on the starter, the engine load, and battery condition. This kind of amperage stresses all of the components in the starter circuit, including the battery, battery terminals, the battery disconnect switch, the cables including the ground path, and any remote solenoids. Problems with these components are hard to find because they appear fine at rest or under a light load, but generate high resistance under heavy amperage draws. The result will be low voltage to the starter during cranking, resulting in heavier amperage draw and increased internal heat in the starter. Over time, this will cause starter failure. Voltage measured at the starter during cranking should always be above 9.5VDC..."
Source: by powermastermotorsports
Has alternator been checked off the Bronco?
You are missing some grounds as you know;
Component Ground Diagram in a 93 w/Out E4OD & Borg Warner ESOF Transfer Case; "...This diagram is compiled for a truck without E4OD or ESOF, and a 4.9L engine; Splice 207 has been corrected, but there could be other minor errors. Note the unnamed connector (C2??) near S207: it's a 1-pin gray connector taped into the main dash harness (14401) 6" left from the chime takeout. It does not show the radio suppression bond straps running from the frame to the body; one goes from the RHF sway bar tab to the core support; another goes from the 3rd LHS body mount bracket to the cab structure..." by Steve83 (Steve, That dirty old truck) at
http://www.supermotors.net/registry/media/907047
Miesk5 Note; see
Radio Bond Strap Diagram
Also, although this is for a 96, Ford incl the 4.9 engine and prob is close enough to use for your 92 4.9; Wiring Harness & Component Location Diagram, Ford Part Numbers, Depictions
Have you tried to start it via the starter relay yet?
Wiring Diagram in 92-95 Bronco
& F Series (detailed, from ign sw thru MLPS (called the PARK/NEUTRAL POSITION SWITCH in this diagram) and to relay & starter motor
Source: by Steve83 (Steve, That dirty old truck) at
http://www.supermotors.net/registry/media/831135
