I have been driving my '89 F150 for almost 2 years now with the "Rear-Anti Lock Brake" light on and decided to do something about it. I printed the entire trouble shooting guide from Mitchell On Demand, had multi meter in hand and was ready to dive in. The first thing I did was to get the codes and could not get any codes, so the first thing was to start checking connections. The first one that I checked and cleaned was for the Master Cylinder Fluid Level Sensor and the started the engine and the LIGHT went out. I took a 40 mile round trip to town and the light has not come back on! I'm glad that light is out, now I have to go cut the grass (no simple fix for this problem).

 

Sometimes just diving in is half the battle. Good to hear about your fix.

 

Moved to proper forum.

 

did you have both red brake light and RABS light on?
Can I get a copy of diagnose printout?

 

The only light that was on was the RABS, i cannot send you a copy because I work for a nationwide company and its printed on their letterhead.If you have any questions I will try to help.

 

Thanks for responding.
I have both red brake light and RABS light on currently, RABS does off and on at start but stays on.
I couldn't get any code. how can I test fluid level sensor? there is no positive in any of 3 wires that goes to brake fluid sensor when I checked with a light tester.
Maybe I should just go buy a Mastercylinder assy and turn it upside down so float will be up and connect to the 3 wire connector to see what hapens?

 

I suppose the problem is not within RABS when code doesn't flash.

 

That should be correct.

 

I think you have to induce the system to blink out the codes. The following procedure for pulling RABS codes should work:

http://fords.kilonet.org/ken00/RABSSOP.doc

Here are the codes:

RABS DIAGNOSTIC TROUBLE CODE CHART (COMPONENT)

11 (ABS Module)

16 (System OK)

17 (Reference Voltage Problem)

22 (LH Front Inlet Valve)

23 (LH Front Outlet Valve)

24 (RH Front Inlet Valve)

25 (RH Front Outlet Valve)

26 (RH Rear Inlet Valve)

27 (RH Rear Outlet Valve)

28 (LH Rear Inlet Valve)

29 (LH Rear Outlet Valve)

31 (LH Front Sensor)

32 (RH Front Sensor)

33 (RH Rear Sensor)

34 (LH Rear Sensor)

35 (LH Front Sensor)

36 (RH Front Sensor)

37 (RH Rear Sensor)

38 (LH Rear Sensor)

41 (LH Front Sensor)

42 (RH Front Sensor)

43 (RH Rear Sensor)

44 (LH Rear Sensor)

51 (LH Front Outlet Valve)

52 (RH Front Outlet Valve)

53 (RH Rear Outlet Valve)

54 (LH Rear Outlet Valve)

55 (LH Front Sensor)

56 (RH Front Sensor)

57 (RH Rear Sensor)

58 (LH Rear Sensor)

61 (FLS Circuits)

62 (Travel Switch)

63 (Pump Motor Speed Sensor)

64 (Pump Motor Pressure)

67 (Pump Motor Relay)

71 (LH Front Sensor)

72 (RH Front Sensor)

73 (RH Rear Sensor)

74 (LH Rear Sensor)

75 (LH Front Sensor)

76 (RH Front Sensor)

77 (RH Rear Sensor)

78 (LH Rear Sensor)

 

I did not get any codes, so I was going to trouble shoot the system and started with the M/C sensor connection and problem solved. Clean your connection and use a clean rod to see if the float is stuck.

 

I really want to work on the truck and get this fixed but pregnant wife wants to go to county park since weather is so nice today! hopefully I can come home before 4 so I have a few hours to work on this. Everyone's input has been much appreciated.

 

I swapped the fluid level sensor with my 91 Mazda Navajo(same as explorer) and problem solved. Thanks for your help!