Help me troubleshoot my ABS!!! - Ranger-Forums - The Ultimate Ford Ranger Resource


General Technical & Electrical General technical and electrical discussion for the Ford Ranger that does not fit in any other sub-forum.

Reply
 
LinkBack Thread Tools Search this Thread
  #1  
Old 02-08-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
Help me troubleshoot my ABS!!!

97 shortbed single cab 2wd ranger with 2.3L and the REAR ANTILOCK BRAKES. I got an ABS light, grounded the fuse in the box and got code 12. I'm trying to troubleshoot the sensor in the brake fluid resivior. It has a three prong connector. On the resivior, the pin closest to the front of the truck, well call it pin #1 I get continuity to pin #2 and nothing on #3. Thinking that i would get a variable ohm reading on it while i push the float i tested each pin while moving the float and nothing. Just constant continuity between pin one and two. On the plug side that goes to the harness, the part that plugs into the resivior I get battery voltage on pin #1, like 105 ohms on pin #3 and no continuity to ground on #2.

I thinking that cause there is no change in ohms across that float its bad and that's why it's throwing the code 12. Somebody wanna check there's and compare notes???

Is there a way to reset the ABS codes so I can see if it comes backa or not? You guys think I'm on the right Track????

Any opinions or ideas are appreciated. Beauty of the internet is I don't like it, I don't have to read it.
Reply With Quote
  #2  
Old 02-08-2012
Clinton's Avatar
Member
iTrader: (19)
 
Join Date: Dec 2010
Location: PA.
Posts: 1,417
Is your ABS light and parking brake light coming on or just the ABS light?
Reply With Quote
  #3  
Old 02-08-2012
StxDangerRanger's Avatar
RF Veteran
iTrader: (2)
 
Join Date: Dec 2010
Location: Flat Rock, Mi
Posts: 6,313
My ABS light goes on and off at will.
Heres a few things that may or may not help:
Your fluid levels have to be pretty exact, not enough brake fluid will cause the light to come on sometimes because of the sensor in the resivior.
Theres also a sensor in the top of the rear axle. Those are known to get a bit dirty and cause a failure. If you pull it out and clean it, you can sometimes shut off the light.

I've never had a problem with the master cylinder sensor, but you might be on to something.
Reply With Quote
  #4  
Old 02-08-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
Quote:
Originally Posted by Hooligan View Post
Is your ABS light and parking brake light coming on or just the ABS light?
Just the ABS light
Reply With Quote
  #5  
Old 02-08-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
Quote:
Originally Posted by StxDangerRanger View Post
My ABS light goes on and off at will.
Heres a few things that may or may not help:
Your fluid levels have to be pretty exact, not enough brake fluid will cause the light to come on sometimes because of the sensor in the resivior.
Theres also a sensor in the top of the rear axle. Those are known to get a bit dirty and cause a failure. If you pull it out and clean it, you can sometimes shut off the light.

I've never had a problem with the master cylinder sensor, but you might be on to something.
Hell, it's worth a try. I didn't think it was the sensor in the tail cause of the #12 code. I'll clean it off and post back.
Reply With Quote
  #6  
Old 02-08-2012
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Brake fluid level switch and connector wiring are as follows:

Dark Green with yellow stripe wire = 12v from fuse 11 (7.5amp) IP fuse panel through warning lamp in dash and RABS Resistor bypass and RABS Diode. If you ground this wire the brake warning light should come on in dash.

Tan with Light Green stripe wire = goes to the RABS module pin 2, low fluid monitoring circuit. This wire is also connected to the ignition switch that provides Chassis Ground with the key in Crank position (G104) testing the bulb functionality during crank.

Solid Black wire = Chassis Ground (G104)

The switch is a shunted 3 pin SPST and is N.O. The switch is internally shunted between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire (pass through to RABS Module pin 2).

If the fluid is low, the switch will close effectively connecting both the Dark Green with Yellow stripe wire and the Tan with Light Green stripe wire (via the shunt) to the Solid Black wire (Ground), illuminating the brake warning lamp in the dash and 0 voltage at pin 2 at the RABS Module. This will also disable the RABS system setting off the ABS warning light.

If this happens after setting the parking brake either the RABS resistor is open and or the diode is conducting in both directions. If you place a bare metal jumper between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire at the connector and then using a DVM set to read 12v, connect the red probe to this jumper and the black probe to ground. You should read 12v. Set the E-Brake while watching the meter. If the voltage drops to 0v check the resistor and diode.
Reply With Quote
  #7  
Old 02-09-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
Quote:
Originally Posted by Rev View Post
Brake fluid level switch and connector wiring are as follows:

Dark Green with yellow stripe wire = 12v from fuse 11 (7.5amp) IP fuse panel through warning lamp in dash and RABS Resistor bypass and RABS Diode. If you ground this wire the brake warning light should come on in dash.

Tan with Light Green stripe wire = goes to the RABS module pin 2, low fluid monitoring circuit. This wire is also connected to the ignition switch that provides Chassis Ground with the key in Crank position (G104) testing the bulb functionality during crank.

Solid Black wire = Chassis Ground (G104)

The switch is a shunted 3 pin SPST and is N.O. The switch is internally shunted between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire (pass through to RABS Module pin 2).

If the fluid is low, the switch will close effectively connecting both the Dark Green with Yellow stripe wire and the Tan with Light Green stripe wire (via the shunt) to the Solid Black wire (Ground), illuminating the brake warning lamp in the dash and 0 voltage at pin 2 at the RABS Module. This will also disable the RABS system setting off the ABS warning light.

If this happens after setting the parking brake either the RABS resistor is open and or the diode is conducting in both directions. If you place a bare metal jumper between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire at the connector and then using a DVM set to read 12v, connect the red probe to this jumper and the black probe to ground. You should read 12v. Set the E-Brake while watching the meter. If the voltage drops to 0v check the resistor and diode.
Awesome. I will try it in the morning and post!
Reply With Quote
  #8  
Old 02-09-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
REV, didn't get a chance to go through it per your instructions, but this morning I jumped the green and tan wires to trick the computer into thinking the resivior is full. ABS light went off. Pulled the jumper and ABS light back on.
Reply With Quote
  #9  
Old 02-09-2012
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Quote:
Originally Posted by LastStarfighter View Post
REV, didn't get a chance to go through it per your instructions, but this morning I jumped the green and tan wires to trick the computer into thinking the resivior is full. ABS light went off. Pulled the jumper and ABS light back on.
Eric,

If you pulled the plug with the key on or switched the ignition on after, the RABS will think the fluid is low or a malfunction has occurred. In this case the red brake warning light will not illuminate. However, in short order the ABS light will come on indicating the system has been disabled. By placing the jumper between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire the RABS system thinks all is well again and turns the light off or will if you cycle the ignition off then back on.

The first thing you need to determine is whether or not the solid black wire has continuity to chassis ground at all times. If not, you'll need to figure out where the open circuit is and fix it.

Next, identify which pins in the sensors connector (M/C Reservoir) correspond to the Dark Green with Yellow stripe and the Tan with Light Green stripe wires. Using your DVM, probe the two pins checking for continuity across the internal shunt. If you don't have continuity between the two pins, you'll need to replace the sensor (M/C Reservoir).

Next, check for continuity between one of those pins and the one the solid Black wire would go to. Depending on how you manipulate the sensor, it will either read continuity or open.

Next, as stated in my last post, with the key off, install the jumper between the Dark Green with yellow stripe wire and the Tan with Light Green stripe wire. Turn the key to the run position. Hook your DVM red probe to this jumper and the black to ground. You should read close to battery voltage (12v). Next while watching the meter, apply your parking brake. If the voltage drops down close to or 0v you'll need to check the resistor and or diode in the Power Distribution Box under hood.
Reply With Quote
  #10  
Old 02-09-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
I got the continuity on the two wires shunted together in the sensor but between that and the other pin nothing when I move the float. I'll do the rest in the morning and let you know. Since the switch isn't working I know I have to replace that. The wire that is supposed to be grounded doesn't have continuity to ground, it's at 105 ohms so even if I replace the sensor it might not work as far as letting me know the fluid is low, but I didn't know if I was supposed to have continuity or not. Schematics especially auto ones don't always show every diode and resistor.
Reply With Quote
  #11  
Old 02-10-2012
StxDangerRanger's Avatar
RF Veteran
iTrader: (2)
 
Join Date: Dec 2010
Location: Flat Rock, Mi
Posts: 6,313
Hm, funny thing.
I went out and checked the ground wire in my sensor, since my ABS light was on again.
Turns out i didn't have ground.
Thanks JJ.
Reply With Quote
  #12  
Old 02-10-2012
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Quote:
Originally Posted by StxDangerRanger View Post
Hm, funny thing.
I went out and checked the ground wire in my sensor, since my ABS light was on again.
Turns out i didn't have ground.
Thanks JJ.
Not a problem...Glad the info was able to help you out. You might want to check the ground point in the engine compartment on the LH side of the rad core support.

Quote:
Originally Posted by LastStarfighter View Post
I got the continuity on the two wires shunted together in the sensor but between that and the other pin nothing when I move the float. I'll do the rest in the morning and let you know. Since the switch isn't working I know I have to replace that. The wire that is supposed to be grounded doesn't have continuity to ground, it's at 105 ohms so even if I replace the sensor it might not work as far as letting me know the fluid is low, but I didn't know if I was supposed to have continuity or not. Schematics especially auto ones don't always show every diode and resistor.
Did you have any success with your problem? Did those diagrams help?
Reply With Quote
  #13  
Old 02-10-2012
Member
Thread Starter
 
Join Date: Feb 2012
Location: Fort Riley KS
Posts: 56
JJ, you are the mother-lovin man! After the trouble shooting I did I went ahead and bought a new sensor. The guy at FoMoCo tells me you plug that in and it's yours man, no returns after that. So I'm home and I'm lookin at the old one and I'm lookin at the new one, about to plug it in and I'm like, well that Rev guy on the ranger-forums said to do it a different way. Did it just like you said and it was the sensor, switched it and bingo, no light. 388,000 and still rolling. I love this truck.

I had the schematics, but thanks. That's what I was using for trouble shooting. I'm glad you kept me straight Rev, Tango Mike.
Reply With Quote
  #14  
Old 07-16-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
I realize that this is an old thread, but I hope Rev or someone who understands the ABS system can help me. I have a 1996 Ranger XLT, 2WD, 3.0 manual. I have read Rev's posts on troubleshooting ABS and have found it to be very helpful. So Rev if you are reading this post or someone familiar with the 2WD ABS I would very much appreciate your help because I have run out of ideas of what to do next.

Here is the situation based on your previous posts in 2012: ABS light ON - Code 12 - "low hyd. fluid" . Fluid level is OK. MC level sensor is not working. Fluid level connector wires T/LG and DG/Y connected together DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but off at idle. Black wire to ground is OK. ABS resistor and diodes are OK - both new. T/LG and DG/Y connected together and DVM used to measure them to ground reads 11.34 V - seems OK with E-Brake set reads 6.8V - seems OK again. PB red light works fine.

Can not get Brake light to come on if DG/Y is grounded. Can not get ABS light to come on when T/LG is grounded. No short in these wires.

Ignition switch is worn and loose - has been for years. Replaced rear speed sensor in differential. Had a lot of iron filings on old one. ABS light has been funny for years. It would always come on if I did not release EB within 2-3 seconds. I would then have to restart engine and ABS light would go off and stay off - now it just stays on after a good cycle test.

I am wondering if I have had two or more problems with the system and I found one with a bad float and now have to resolve another one?

Could the CM be bad?

Thanks for anyone's help. I have been working on this problem for a ton of hours and I am just stumped.

Glenn

Last edited by Glenn Ford; 07-16-2014 at 09:05 PM.
Reply With Quote
  #15  
Old 07-17-2014
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Quote:
Originally Posted by Glenn Ford View Post
Fluid level connector wires T/LG and DG/Y connected together DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but off at idle.
Are you stepping on the brake pedal at any point?


Quote:
Originally Posted by Glenn Ford View Post
Can not get Brake light to come on if DG/Y is grounded. Can not get ABS light to come on when T/LG is grounded. No short in these wires.
With the ignition on, wiring connector disconnected from the MC sensor, grounding the DG/Y wire should cause the red light to come on.

Quote:
Originally Posted by Glenn Ford View Post
Ignition switch is worn and loose - has been for years.
If its just the key cylinder it shouldn't effect it. However, if its the ignition switch it could but, I'd suspect you'd have other symptoms.

Quote:
Originally Posted by Glenn Ford View Post
Could the CM be bad?
Based on your description I'd be inclined to say yes. However, if you cant get the red brake light to come on when grounding the DG/Y wire that needs to be looked into further before condemning the module.
Reply With Quote
  #16  
Old 07-17-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
Quote:
Originally Posted by Rev View Post
Are you stepping on the brake pedal at any point?

Yes, I could have - only when testing the ABS light.


With the ignition on, wiring connector disconnected from the MC sensor, grounding the DG/Y wire should cause the red light to come on.

I did not have the ignition on - will test again.

If its just the key cylinder it shouldn't effect it. However, if its the ignition switch it could but, I'd suspect you'd have other symptoms.

OK.

Based on your description I'd be inclined to say yes. However, if you cant get the red brake light to come on when grounding the DG/Y wire that needs to be looked into further before condemning the module.
I will look into it again.

Thanks for your help - some more work to do.
Reply With Quote
  #17  
Old 07-18-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
I do not understand if I connect the Fluid level connector wires T/LG and DG/Y together they DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but light is off at idle. No brake. Any help.

Quick after thought - could my ABS relay in the PDB be bad?

Glenn

Last edited by Glenn Ford; 07-18-2014 at 11:53 AM.
Reply With Quote
  #18  
Old 07-19-2014
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Quote:
Originally Posted by Glenn Ford View Post
I do not understand if I connect the Fluid level connector wires T/LG and DG/Y together they DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but light is off at idle. No brake. Any help.

Quick after thought - could my ABS relay in the PDB be bad?

Glenn
Glenn,

unless your truck is 4 wheel drive it more than likely only has RWAL (no relay).

You should have both a yellow light (ABS) and a red light (Parking brake / low fluid reservoir).

Shoot me an email address by PM and I'll send you the wiring schematics.
Reply With Quote
  #19  
Old 07-19-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
Ranger is 2WD.

I still do not understand if I connect the Fluid level connector wires T/LG and DG/Y together they DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but light is off at idle. No brake.

Email: [email protected] Thanks.
Reply With Quote
  #20  
Old 07-19-2014
Rev's Avatar
Rev Rev is offline
Level I Supporter
 
Join Date: May 2005
Location: San Diego, CA
Posts: 1,179
Quote:
Originally Posted by Glenn Ford View Post
Ranger is 2WD.

I still do not understand if I connect the Fluid level connector wires T/LG and DG/Y together they DO NOT permanently turn off the ABS light. Light comes on as soon as truck is moved - but light is off at idle. No brake.

Email: [email protected] Thanks.
Glenn,

Email sent.
Reply With Quote
  #21  
Old 07-20-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
I believe it is the brake proportioning valve. Seems to be down to that.
Reply With Quote
  #22  
Old 08-05-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
Update: I replaced the ABS proportioning brake valve and no more ABS light for the first time in probably 5 years. I guess it was the valve all along.

One remaining issue if anyone can help me with is that I now notice a pronounced click when I put the brakes on. It is not coming from the PV. In fact, if I put my hand on the brake petal and push on it I can feel a definite click vibration in the brake petal. It sounds like it is coming from the area under the hood of the MC or vacuum booster. I did overfill the MC a little - can not believe that did it? Any suggestions?

Thanks for everyone's help in this repair.

Glenn
Reply With Quote
  #23  
Old 10-08-2014
Member
 
Join Date: Oct 2014
Location: Indiana, PA
Posts: 1
I hate to be one of those folks who joins a forum and starts immediately asking for help, but recently I bought a '96 Ranger XLT as a roustabouter. I'm trying to work out an ABS that's pitching a Code 12.

While troubleshooting the brake fluid level sensor, everything seems to be checking out continuity-wise except the the DG/y wire is only showing 8-10 volts, which later drops to 4 or so when the PB is applied.

Sort of suspecting it might be in the ignition, that it might be partially grounding circuit. Other peculiarities I've noticed is when I push down on the float in the MC reservoir, the red brake light will come on...faintly, as opposed to bright red when the PB is engaged. Also, though it might not be related, my gas gauge acts strangely. Turn the key off, it reads (not sure if it's supposed to do this or flatline), turn the key on and it goes to nothing. I bob up and down on the bed, thinking the slosh would at least make the needle bobble...nothing.

Any ideas about it being something other than ignition-related?

It's a 1996 Ranger XLT, 2.3, Manual.
Reply With Quote
  #24  
Old 10-08-2014
Member
 
Join Date: Jul 2014
Location: McDonough, GA
Posts: 15
I can tell you from my frustrating experience with my ABS light for 5 years and my lack of common sense approach to solve the problem even in light of the correct information given to me on this board. Regardless of all the posts and work I did on my Ranger, I continued to ignore the obvious sign that the problem was the MC reservoir sensor. I replace the Differential sensor and the Proportioning Valve and foolishly wasted a great deal of money. I thought I solved the problem after I installed a new PV because the ABS light did not come on for 40 miles, but it did come back.

I tested the MC reservoir sensor and got mixed results on if it was good or not. I finally got some sense and replaced the sensor and fixed the problem. Note: You can not replace the sensor on 1996 Rangers - you must replace the entire MC and reservoir. I originally hesitated to replace the MC because I knew from past experience that I could have a serious problem getting the brake line fittings on correctly without cross threading them. Of course, I did have a serious problem threading one of the fittings. I had to completely remove the MC and thread this one fitting in while I held the MC in my head. Code 12 is USUALLY the MC reservoir sensor - rarely anything else especially if the MC is old or never been replaced.

Last edited by Glenn Ford; 10-08-2014 at 02:20 PM.
Reply With Quote
  #25  
Old 05-06-2015
Member
 
Join Date: May 2015
Location: norfolk VA
Posts: 1
does parking brake warning light malf. factor in?

Similar issue above thread, will start troubleshooting this weekend, checking to make sure nothing else to consider.
1. 2 weeks ago replaced front pads. When done noticed that whoever owned the truck before me topped off the fluid level, because it overflowed. Siphoned off extra. all seemed well.

2. noticed a short time ago that the parking brake activation did not trigger warning light. Assumed it was stuck sensor, plan to hit with a bit of WD40.

3. Now getting brake and ABS light.

will use above assistance to check the master cylinder level sensor (fluid is about 1/4 inch from max level) and also (since I am planning on selling truck to a relative before deploying overseas) check rear brakes for any obvious issues.
Reply With Quote
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Help Troubleshoot AC dan1326 General Ford Ranger Discussion 3 08-06-2015 07:23 AM
2000 Ranger 2 wheel abs or 4 wheel abs?? Please help NedoMedo Suspension Tech 6 02-23-2012 06:04 PM
Help me troubleshoot this. Vonhanson 8-Cylinder Tech 4 02-20-2012 11:11 PM
how do i troubleshoot carburetor backfire, exaust backfire, and acceleration issues corey1991 SOHC - 2.3L & 2.5L Lima Engines 2 10-15-2010 05:26 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -6. The time now is 06:09 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.