My ABS Warning Light stays on all the time. However, I have noticed no problems with braking. Any idea what may be causing the light to stay on. Any troubleshooting advise would be appreciated

 

ABS light is for the Anti Lock portion of your brakes...they may work fine but the anti lock is prolly dead. Could be all sorts of things...best is to get a book for your truck and start with the guides they have in there. Its prolly just some $20 sensor that needs replaced.

 

A little more information would be helpful--what year? Does the light come on when you turn the truck or after you first hit the brakes?

 

Have you noticed your speedometer bouncing or doing anything weired? I have heard a lot of the rear axle sensor going out. It is the signal for both the rear ABS and speedo.

 

My light has been on for almost 9 years now and I just don't worry about it even though I think about it all the time. From what I have read on the same scenarios on this forum, there is an ABS sencor on the top of the rear diff that could be dirty or bad. I cleaned mine easily but did't correct the problem. Anyway, I do plan on replacing mine in the next couple of weeks and I'll let you know if it makes a different. Let us know if you get it corected.

 

Did you check the fuse? Someone 'borrowed' the fuse out of my '95. ABS light stayed on until replaced.

 

I have a '94 EB. I had a 15a fuse in the box over the driver's side wheel well go out. It feeds the ABS/ reverse lights/ HEGO/ MLPS and causes the speedo and mileage guages to not work. I am still troubleshooting the cause of the burned fuse but suspect the HEGO. All the sensors and harnesses seem to be in good shape. I have replaced the 15a fuse three times, once lasted a week, second 15 minutes and so far the third has not blown. (3 days +) I installed a 5a fuse in-line with the HEGO for troubleshooting, waiting to see how long it lasts. I am currently researching to see if others have had this problem.

 

Clever idea putting a fuse inline with the HEGO. But, unless I'm mistaken, isn't it recommended to not tamper with the HEGO wiring because the signal is so small and it's very sensitive to additional resistance?

 

Good point. My thought is the fuse on the 12v supply side shouldn't effect the signal side of the HEGO. The worst I expect is for the sensor to be intermittent, short and burn the fuse and I lose the sensor until I replace with a new sensor. According to my wiring diagram, the HEGO has 12v input, ground and two signals out.

 

My ABS light would turn on. But then the speedo would bounce around. Then it would go out completely and it wouldn't change gear. The O/D light would flicker. I would turn it off and everything would reset until the next outbreak. I changed the speed sensor, but it continues. I have a 96 bronco XLT. Is it an electrical problem or mechanical. Help me out fellas.

 

Mine is on all the time. My wheels bearings went, in a short period of time due to water contamination, or improper spindel nut torque, or both, not sure. The spindle got buggered up, along with eferything else in there. The ABS sensors were ground up, hence the light stays on. It's probably the sensors. Does the abs still work? I'm pretty sure I have rear abs only now, it seems to still work in the snow.

 

My ABS light stays on but only when I start rolling. Any ideas? When I first start her up and look at the dash the light is off.. but as soon as I start moving it lights up. Could it be just the sensor?

 

On your '95, you should have 4-wheel ABS. It's probably coming on when you start rolling because it's getting bad feedback (or none) from one of the wheels. Pull the ABS codes to see which wheel it is, then check it out. Could be a bad sensor, or a dirty sensor or tone ring.

Here's the test connector:
http://www.superford.org/registry/ve....php?id=111586
Jumper pin B to E, turn the key on, then remove the jumper after 5 seconds or more. Watch the codes flash on the ABS light; they'll be 15 seconds apart.

SYMPTOM CHART — 4-WHEEL ANTI-LOCK BRAKES Condition Possible Source Action
Code 11 Retrieved
Anti-lock brake electronic control module failure.
REPLACE anti-lock brake electronic control module.

Code 16 Retrieved
System OK.
None.

Reference Voltage/Intermittent Valve Fault (Code 17)
30 amp fuse open.
Intermittent connections to battery, main relay or ground.
Main relay coil or contacts open.
Open or short to ground in Circuit 532 (O/Y).
Open or short to ground in Circuit 599 (PK/LG).
Open or short to ground in Circuit 601 (LG/PK).
Short to ground through anti-lock hydraulic control unit.
Intermittent valve failures.
High resistance valves.
GO to Pinpoint Test A .

Front Left Inlet Solenoid Valve Concern Diagnosis (Code 22)
Intermittent open Circuit 495 (T).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 40.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 6.
Open or shorted inlet front left valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test B .

Front Left Outlet Solenoid Concern Diagnosis (Code 23)
Intermittent open Circuit 496 (O).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 26.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 7.
Open or shorted outlet front left valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test C .

Front Right Inlet Solenoid Valve Concern Diagnosis (Code 24)
Intermittent open Circuit 497 (W).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 34.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 8.
Open or shorted inlet front right valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test D .

Front Right Outlet Solenoid Valve Concern Diagnosis (Code 25)
Intermittent open Circuit 498 (PK).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 15.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 5.
Open or shorted outlet front right valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test E .

Rear Axle Inlet Solenoid Valve Concern Diagnosis (Code 26)
Intermittent open Circuit 499 (GY/BK).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 33.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 2.
Open or shorted inlet rear axle valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test F .

Rear Axle Outlet Solenoid Concern Diagnosis (Code 27)
Intermittent open Circuit 510 (T/R).
Terminal backout in anti-lock brake electronic control module connector Pins 17 and 27.
Terminal backout in anti-lock hydraulic control unit connector Pins 1, 4 and 3.
Open or shorted outlet rear axle valve coil.
Open or shorted driver in anti-lock brake electronic control module.
GO to Pinpoint Test G .

Left Front Brake Anti-Lock Sensor Diagnosis (Static) (Code 31)
Poor connection at left front brake anti-lock sensor.
Terminal damage or backout in anti-lock brake electronic control module connector Pins 24 and 25.
Terminal damage or backout in two-pin sensor connector.
Open or shorted left front brake anti-lock sensor.
Open or shorted Circuit 521 (T/O) or 522 (T/BK).
Improper front left anti-lock brake sensor cable routing leading to above.
Defective front left wheel speed sensor electrical test circuit in anti-lock brake electronic control module.
GO to Pinpoint Test H .

Right Front Brake Anti-Lock Sensor Diagnosis (Code 32)
Poor connection at right front brake anti-lock sensor.
Terminal damage or backout in anti-lock brake electronic control module connector Pins 36 or 23.
Terminal damage or backout in two-pin anti-lock brake sensor connector.
Open or shorted right front brake anti-lock sensor.
Open or shorted Circuit 514 (Y/R) or 516 (Y/BK).
GO to Pinpoint Test J .

Rear Axle Speed Sensor Diagnosis (Code 33)
Poor connection at vehicle speed sensor.
Terminal damage or backout in anti-lock brake electronic control module connector Pins 21 or 22.
Terminal damage or backout in two-pin sensor connector.
Open or shorted vehicle speed sensor coil.
Open or shorted Circuit 518 (LG/R) or 519 (LG/BK).
Improper vehicle speed sensor cable routing leading to above.
Defective vehicle speed sensor electrical test circuit in anti-lock brake electronic control module.
NOTE: Some vehicles were built using Circuit 523 (R/PK) in place of 518 (LG/R).


GO to Pinpoint Test K .

Left Front Brake Anti-Lock Sensor Diagnosis (Dynamic) (Codes 35, 41, 55, 75)
Damaged/missing front brake anti-lock sensor indicator teeth or missing front brake anti-lock sensor indicator.
Air gap too small or too large.
Excessive axle vibration.
Weak front brake anti-lock sensor.
Loose front brake anti-lock sensor.
INTERMITTENT short or open in Circuit 521 (T/O) or 522 (T/BK).
Disturbances caused by ignition or radio frequency interference.
Defective trigger circuit in anti-lock brake electronic control module.
GO to Pinpoint Test L .

Right Front Brake Anti-Lock Sensor Diagnosis (Dynamic) (Codes 36, 42, 56, 76)
Damaged/missing front brake anti-lock sensor indicator teeth or missing front brake anti-lock sensor indicator.
Air gap too small or too large.
Excessive axle vibration.
Weak front brake anti-lock sensor.
Loose front brake anti-lock sensor.
INTERMITTENT short or open in Circuit 514 (Y/R) or 516 (Y/BK).
Disturbances caused by ignition or radio frequency interference.
Defective trigger circuit in anti-lock brake electronic control module.
GO to Pinpoint Test M .

Rear Axle Speed Sensor Diagnosis (Dynamic) (Codes 37, 43, 57, 77)
Damaged/missing indicator ring teeth or missing indicator ring.
Air gap too small or too large.
Excessive axle vibration.
Weak rear axle sensor.
Loose rear axle sensor.
Intermittent short or open in Circuit 518 (LG/R) or 519 (LG/BK).
NOTE: Some vehicles were built using Circuit 523 (R/PK) in place of 518 (LG/R).



Disturbances caused by ignition or radio frequency interference.
Defective trigger circuit in anti-lock brake electronic control module.
GO to Pinpoint Test N .

Hydraulically Inoperative Front Left Outlet Valve or Sensor Disturbance Detected Diagnosis (Code 51)
Pinched or closed brake line or hose.
Worn or clogged front left outlet valve.
GO to Pinpoint Test P .

Hydraulically Inoperative Right Front Outlet Valve or Sensor Disturbance Detected Diagnosis (Code 52)
Pinched or closed brake line or hose.
Worn or clogged front right outlet valve.
GO to Pinpoint Test Q .

Hydraulically Inoperative Rear Axle Outlet Valve or Sensor Disturbance Detected Diagnosis (Code 53)
Pinched or closed brake line or hose.
Worn or clogged rear axle outlet valve.
GO to Pinpoint Test R .

Pump Motor Triggered but Did Not Run (Code 63)
Damaged pump motor.
Terminal backout in anti-lock brake electronic control module harness connector Pins 17, 29, 37 and 38.
Open or shorted pump motor relay coil.
Open contacts in pump motor relay.
Terminal backout in pump motor 4-way, Pins 1, 2, 3 or 4.
GO to Pinpoint Test S .

Acceleration Sensor (Code 65)
Terminal backout in anti-lock brake electronic control module wiring harness connector Pins 30, 31 and 32.
Worn or damaged acceleration switch.
Worn or damaged anti-lock brake electronic control module.
Acceleration switch terminal backout, Pins 1, 2 and 3.
Short to ground in Circuits 836 (O/W), 886 (O/BK) and 887 (Y).
GO to Pinpoint Test T .

Pump Motor Running but Not Triggered (Code 67)
Damaged trigger circuit in anti-lock brake electronic control module.
Terminal backout in anti-lock brake electronic control module harness connector Pins 2 and 3.
Welded relay contacts.
Short to ground in Circuit 539 (PK/LB).
GO to Pinpoint Test U .

Amber ABS Warning Lamp On, No Code
Worn or damaged ignition switch.
Open ignition feed circuit to anti-lock brake electronic control module.
Low battery voltage (less than 8V).
Blown ignition fuse.
Open system ground.
GO to Pinpoint Test V .