Rear Antilock Brake Light and Cruise Control?

[Pono]

Hello forum,

I am new to the site. I have a 1989 4x4 2.9 Ranger. Truck is all original and in good shape. Daily driver with over 200,000 miles. I recently replaced the starter and solenoid. During the test drive the rear antilock brake light came on and the cruise control stopped working. Not sure what I could of influenced to cause this. The wire that is near the starter that exits from the oil pan (I am assuming a oil level sensor did get disturbed). Could this influence the antilock light?
I replaced the rear sensor that attaches to the rear end. It did not make a difference.

Also checked the fuses under the dash.

Any advise would sure be appreciated.
Thank you,

John
Big Island Hawaii

 

[Josh B]

Hey Pono, very nice truck! Welcome to TRS
It's well after midnight here in central US, I suppose you've stepped out to watch the sun set, must be nice.
I can't help with a solution, but in time someone surely will

 

[RobbieD]

Welcome, and that's a nice Ranger you got there.

Considering that the antilock light and cruise not working seem related, a couple of things to check are:

Are you brake lights functioning correctly? Both systems use the brake on/off (BOO) switch.

Make sure that the wiring plug on the fluid reservoir didn't get dislodged when you changed the starter. Low fluid level should throw the red brake light, but the antilock indicator light also touches this switch.

Is your parking brake indicator functioning? (red brake light when applied, key on). This shouldn't affect the cruise, but it can affect the antilock.

A fault code can be pulled from the antilock system via the antilock light, but it just seems too much of a coincidence that you have cruise and antilock issues after an unrelated repair.

 

[Pono]

Mahalo for the replies. On the road until after TG. Will check out your advise Robbie when I get home. Nice list of new Rangers buy the way!

 

[RobbieD]

Have a great and safe holiday, and do let us know what you find when you can get back to it.

 

[Pono]

Had a chance to trouble shoot a few items on the Ranger. Checked the brake reservoir level and connector, removed the wire on the engine oil sensor and checked it since it is near the starter and I could have dislodged it. I actually removed it and grounded it to see if I would get a check oil indication. Checked fine. Rear brake lights work fine. Parking brake indicator is working fine. Will try and get a code of the anti lock brake light next.

 

[Pono]

I also replaced the magnetic sensor on the rear differential. Do you guys think I should take the cover off the back and clean the pick up ring?

 

[pjtoledo]

the ring is bathed in gear lube as it rotates. I would not expect it to be contaminated.
in the new-problem-after-work situation I would look for a dislodged wire or connector near wherever you had your hands/tools under the truck.

 

[RobbieD]

Good to hear back from you, Pono. Sounds like you've covered some good ground troubleshooting so far. But I have to agree with the previous, to double-check anywhere you may have been when you changed the starter and solenoid. And it would be a good idea to check what antilock fault code is present. Good luck!

 

[Pono]

I used a short wire to plug into the OBD plug and pulled code 67 which I believe is the neutral safety switch. This may have been due to it not being in neutral when checking the codes. Nothing came up associated with the rear antilock brake light. Wondering will the code show up if the rear antilock brake light is not on. It takes driving the truck for ten to fifteen minutes before the light comes on. Once I turn the key off the light turns off. So maybe the jumper wire will not work in this case since I need to count the number of times the check engine light comes on once I turn the key back on.

 

[RobbieD]

Getting a code for the yellow antilock light being on is different than pulling OBD codes, and the light does have to be on. These four pages (from the 1989 Ranger shop manual) will get you started in the right direction. The RABS diagnostic connector should be easy to find, where your main harness comes in through the firewall behind the fusebox. You should be able to download these pages and enlarge them enough to read. The factory instructions are pretty clear, and once you have a RABS diagnostic code we can go from there. Read through these pages and note how the red "brake" light and the yellow "RABS" light are both used to diagnose the system.






One more question: are your rear brakes in good shape, or are the rear brake shoes close to needing replacement?

 

[Pono]

Good information Robbie. Thank you. Will inspect rear brakes. Will get to work on the documents sent also.
John

 

[alwaysFlOoReD]

I copied your pics. Thanks.

Getting a code for the yellow antilock light being on is different than pulling OBD codes, and the light does have to be on. These four pages (from the 1989 Ranger shop manual) will get you started in the right direction. The RABS diagnostic connector should be easy to find, where your main harness comes in through the firewall behind the fusebox. You should be able to download these pages and enlarge them enough to read. The factory instructions are pretty clear, and once you have a RABS diagnostic code we can go from there. Read through these pages and note how the red "brake" light and the yellow "RABS" light are both used to diagnose the system.

View attachment 34538
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One more question: are your rear brakes in good shape, or are the rear brake shoes close to needing replacement?

 

[Pono]

Made some good progress today. The diagnostic connector was easy to find as you mentioned. The code flashed 11 times which indicates "stop lamp circuit defective". I did install some LED bulbs recently. Will do some further research. Your assistance has been incredibly valuable.
-John

 

[Pono]

Just check the stop lights. Both working fine. We put the regular 1157 bulbs on later today and see if it is the lack of resistance from the LED bulbs.
-John