Full Size Ford Bronco Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
834 Posts
Discussion Starter #1
I got a battery drain and i cannot find it, any suggestions ? Thinking of just completely removing all the 41 year wire and going for new either from american wire or painless or if someone has a better suggestion
 

·
Super Moderator
Joined
·
23,936 Posts
Yo Bob,
Following by Ford;
"
  • Battery drain.
  • Open or high resistance in wiring.
  • Damaged regulator.
  • Generator.( as Ford still describes the alternatore:
Battery Testing Procedure TSB 91-10-10 for 85-91 Bronco, Aerostar, Econoline, F-150-350 Series, Ranger; 85-90 Bronco II; 89-91 F Super Duty, F47, F-53, F-59; 91 Explorer, etc.
Source: by Ford

Loose or Weak Contact at Generator Harness Connector TSB 96-21-4 for 86-93 Bronco
Source: by Ford
"ISSUE: When a generator fails, there are a few failure modes that may cause heat to be produced at the wiring harness-to-generator connector. This excess heat may damage the female terminals on the wiring harness, resulting in increased resistance. The increased resistance produces more heat. When the generator is replaced, the resistance produced by a damaged connector may damage the new generator and could result in a repeat repair, including installation of another generator. High resistance (caused by a damaged connector) will not go away until the damaged connector is replaced.
ACTION: Visually inspect the harness-to-generator connector for damage (heat, corrosion, distortion and cracking) before installing a new generator. Install the Generator Wiring Harness Connector Kit (E5AZ-14305-AA) if the harness-to-generator connector is damaged.
The Generator Wiring Harness Connector Kit (E5AZ-14305-AA) contains the following:
One (1) Red Wire Butt Connector
Two (2) Yellow Wire Butt Connectors
One (1) Wire Connector Assembly
One (1) Instruction Sheet (I.S. 6849)
PART NUMBER PART NAME
E5AZ-14305-AA Generator Wiring Harness Connector Kit
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 95-25-04"

Parastic Drain Test by Ford
"Check for current drains on the battery in excess of 50 mA with all the electrical accessories off and the vehicle at rest. Current drains can be tested with the following procedure.
WARNING: DO NOT ATTEMPT THIS TEST ON A LEAD-ACID BATTERY THAT HAS RECENTLY BEEN RECHARGED.
CAUTION: Do not crank the engine or operate accessories that draw more than 10A. You could blow the fuse in the meter.
NOTE: Many computers draw 10 mA or more continuously.
NOTE: Use Rotunda 88 Multimeter 105-R0053 or equivalent between the battery positive or negative post and its respective cable.
NOTE: Steps 1-5 correspond to the numbers in the following illustration.
Insert the test leads in the input terminals shown.
Turn switch to mA/A DC.
Disconnect battery terminal and touch probes as shown.
Isolate circuit causing current drain by pulling out one fuse after another while reading the display.
Welcome and Current reading will drop when the fuse on the bad circuit is pulled.
Reinstall fuse and test components (including connectors) of that circuit to find defective component(s).

Typically, a drain of approximately one amp can be attributed to an engine compartment lamp, glove compartment lamp, or luggage compartment lamp staying on continually. Other component failures or wiring shorts may be located by selectively pulling fuses or disconnecting fuse links to pinpoint the location of the current drain. When the current drain is found, the test lamp will go out or the meter reading will fall to an acceptable level. If the short is still not located, after checking all the fuses and fuse links, the drain may be due to the generator.

Test Conclusion
8The current reading (current drain) should be less than 0.05 amps. If it exceeds 0.05 amps it indicates a constant current drain which could cause a discharged battery. Possible sources of current drain are vehicle lamps (brake lamps, underhood, glove compartment, luggage compartment, etc.) that do not shut off properly.

If the drain is not caused by a vehicle lamp, remove the fuses from the interior fuse junction panel, one at a time, until the cause of the drain is located. If drain is still undetermined, remove fuses one at a time at the main fuse junction panel to find the problem circuit.

Electronic Drains Which Shut Off When the Battery Cable Is Disconnected
Repeat Steps 1 through 6 of the voltmeter drain testing.
Without starting engine, turn ignition on for a moment and then off. If applicable, wait one minute for the illuminated entry lamps to turn off.
Connect the voltmeter and read the voltage.

Test Conclusion
The current reading (current drain) should be less than 0.05 amps. If it exceeds 0.05 amps after a few minutes, and if this drain did not show in previous tests, the drain is most likely caused by a malfunctioning electronic component. As in previous tests, remove the fuses in interior fuse junction panel one at a time to locate the problem circuit."
by Ford


Do you have an under-hood lamp? if so, disconnect it, but be careful of assy since it is prob contains mercury in the switch.
Check glove compartment lamp. It's switch could be misadjusted.
Feel headlight switch panel area w/lights on; if it is very warm, inspect switch, it's connector and harness after connector.
!○
Check both battery posts, cables, connectors & major GROUND cables for looseness and corrosion. If you see corrosion on a cables' wires strands between connectors or lugs and leading into the insulation, peel back the insulation to see how far back it reaches.
by El Kabong @
"Cheesy clamp on end. Do not use for a long term repair. Only to get you home when nothing else is available. If you have one of these, suspect it before anything else" El Kabong @ Common Replies to FAQs

Check starter relay for looseness or rust to the inner fender. It's ground is through its body to the inner fender.
Check that starter is mounted securely and connectors are clean and tight

CHECK GROUND CABLES to frame, block etc.
Slow Cranking or a Grinding Noise; "... Problems with the negative battery cable is a major cause of starting problems in Ford, Lincoln, and Mercury vehicles. Bad battery cables can cause slow cranking or a grinding noise when trying to start an engine. ..,the wire connection inside the battery terminal connector corrodes easily. This will cause a voltage drop in the cable and result in low voltage being supplied to the starter. You can check for voltage drop in the cable using a digital voltmeter. Connect the negative probe of the voltmeter to the negative battery post (not the battery terminal connector). Then connect the positive probe to the starter case and crank the engine. The voltage reading should be less than .5 volts. A higher reading means there is resistance in the cable or the battery terminal connector. Clean the cable end and the battery terminal connector and test again. If the voltage reading is still higher than .5 volts, replace the cable and the battery terminal connector..."
Source: by genco1.com

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

Starter Motor Does Not Crank Engine:
Loose or corroded battery cable connections. Especially grounds from batty post to frame/engine, etc.
Undercharged battery.
Malfunctioning starter relay.
Faulty starter motor ground circuit.
Malfunctioning starter motor.
Malfunctioning ignition switch.

BATTERY DOES NOT HOLD A CHARGE in 92-96
L1 CHECK BATTERY CONNECTIONS

  • Inspect the battery cables for loose or corroded connections.
Are the battery cables clean and tight?
YesNo
GO to L2.CLEAN AND TIGHTEN the battery cables.
L2 CHECK DRIVE BELT TENSION
  • Perform the drive belt adjustment procedure.
Is the drive belt adjusted properly?
YesNo
GO to L3.ADJUST or REPLACE the drive belt.
L3 LOOSE BATTERY POST
  • Check for loose battery posts.
Are posts OK?
YesNo
GO to L4.REPLACE battery.
L4 CRACKED BATTERY COVER
  • Remove battery hold down clamps and shields.
  • Check for broken/cracked case or battery cover.
Are case and cover OK?
YesNo
GO to L5.REPLACE battery.
L5 CHECK BATTERY
  • Perform the battery capacity test. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Is battery OK?
YesNo
GO to L6.REPLACE the battery.
L6 CHECK FOR KEY-OFF DRAIN
  • Perform battery drain test. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Is correct drain less than 50 Ma (or test lamp off)?
YesNo
GO to L7.GO to Component Tests in the Diagnosis and Testing portion of this section to find the cause of key-off battery drain.
L7 CHECK FOR OPEN B+ CIRCUIT
  • Measure voltage at B+ terminal on the back of the generator, Circuit 38 (BK/O).in later years.
Is voltage at B+ terminal equal to battery voltage?
YesNo
GO to L8.CHECK fuse link in Circuit 38 and REPLACE if required. If OK, SERVICE open in Circuit 38 (BK/O).
L8 CHECK FOR OPEN A CIRCUIT
  • Measure voltage at test point A on the voltage regulator.
Is voltage at test point A equal to battery voltage?
YesNo
GO to L9.CHECK fuse in Circuit 36 and REPLACE if required. If OK, SERVICE open in Circuit 36 (Y/W).
L9 CHECK FOR OPEN FIELD CIRCUIT
  • Measure voltage at test point F on the voltage regulator.
Is voltage at test point F equal to battery voltage?
YesNo
GO to L10.GO to L16.
L10 CHECK FOR OPEN I CIRCUIT
  • Key to RUN.
  • Measure voltage at wiring harness I terminal, Circuit 904 (LG/R).
  • NOTE: Voltage regulator must be connected to wiring harness for this test.
Is voltage greater than 1 V?
YesNo
GO to L11.SERVICE open or high resistance in Circuit 904 (LG/R).
L11 CHECK VOLTAGE DROP IN A CIRCUIT
  • Measure voltage drop between test point A on the voltage regulator and the positive (+) battery post.
Is voltage drop less than 0.25 V?
YesNo
GO to L12.SERVICE excess voltage drop in Circuit 36 (Y/W). CHECK fuse and connectors in Circuit 36 and SERVICE as required.
L12 CHECK FIELD TURN-ON
  • Measure voltage at test point F on the voltage regulator.
Is voltage at test point F less than 2 V?
YesNo
GO to L13.GO to L16.
L13 CHECK FOR SHORTED RECTIFIER
  • Remove one-pin S connector from generator.
  • Measure voltage between the S terminal on the back of the generator and ground.
  • Measure voltage between the positive (+) battery terminal and the S terminal on the back of the generator.
Is either voltage reading greater than 1 V?
YesNo
REPLACE generator.GO to L14.
L14 CHECK VOLTAGE DROP IN B+ CIRCUIT
  • Install S connector.
  • Start engine.
  • Turn headlights ON and HIGH blower.
  • With engine running at 2000 rpm, measure voltage drop between the B+ terminal on the back of the generator and the positive (+) battery post.
Is voltage drop less than 0.5 V?
YesNo
GO to L15.SERVICE excess voltage drop in Circuit 38 (BK/O). CHECK fuse link in Circuit 38 and the connections between the battery and power distribution box.
L15 CHECK FOR OPEN STATOR PHASE
  • Connect test point F on the voltage regulator to the negative (-) battery post using a jumper wire.
  • Perform Generator No-Load Test. Refer to Component Tests in the Diagnosis and Testing portion of this section.
Is generator output greater than the minimum output specified?
YesNo
REPLACE voltage regulator.REPLACE generator.
L16 CHECK FOR OPEN/SHORTED FIELD
  • Remove generator from vehicle.
  • Remove voltage regulator.
  • Measure resistance between the generator slip rings.
Is resistance greater than 10 ohms or less than 1 ohm?
YesNo
REPLACE generator.CHECK for worn brushes (less than 8mm long) or open brush leads and REPLACE if required. If OK, REPLACE voltage regulator.
 

·
Registered
Joined
·
416 Posts
Possible a new harness helps, if you’ve got a short somewhere. But that’s an expensive guess.
What have you done to troubleshoot so far?
The electrical systems on our Broncos aren’t terribly complex. Miesk’s info probably references a test light and pulling fuses. Is the battery and charging system in good shape?
 

·
Registered
Joined
·
32 Posts
i think i found it, my radio clock and dash clocks
Did you find it? Hope so. If you didn,t and have a TILT STEERING. Take the cover off the steering wheel and look for a little wire that may have gotten between the spring inside of it and each time you raise or lower the tilt steering.It can cause the wire to pinch a hole in the wire cover.
 
1 - 8 of 8 Posts
Top