1996 bronco5.8 ABS PROBLEM

[tres]

Hi to all.I'm NM Bronco...My past posts have mistakenly not been at this site.Hope the powers to be forgive me for not posting at the correct forum.My problem seems to be at first glance a very simple one,but becomes very complicated as you will soon see.My bronco is a 1996 5.8L with 120000 miles.

While traveling to Grand Junction,CO several weeks ago,and while at a rest stop just south of Moab,UT,when moving forward,I heard a clicking sound coming from what I believed to have been my front left wheel.This was verified to be correct later in the repair process.I drove the 10 or so miles into Moab to get gas...at this point I felt the front left-hub...it felt as if it were on fire.The front right hub was not as hot,but I could not keep my fingers for less than a split second.I had to get to GJ,CO so I let the vehicle cool for another 20 minutes or so.I got to GJ without a problem,and took the bronco to a garage the next morning.My son had used this garage for years and put his total trust in the mechanics.They removed the rotors..they were scared to almost nothing,as well as they replaced the pads,and calipers.Of course the fluid was drained and replaced as well as they had checked the rear brakes which they found to be ok.When on a test drive the next day(it was Friday) the ABS system was malfunctioning(the light was on,and by the way,the ABS light never came on until this point). The brakes begain to pulsate when the pedal was depressed..it felt as if the brakes wanted to lock up.Also,the bronco was pulling hard to the right..lots of ****-like motions before coming to a complete stop.The clicking noise in the front left wheel (drivers side) continued.The computer as I understand it was giving readings indicating a problem with the sensors.New sensors where ordered from Denver,and placed on the vehicle...the problem contonues.Had gone to Glenwood Springs,CO for the weekend.Now its Monday.The Bronco was taken to a Napa Shop next door and their computer was giving the same readouts..On Tuesday,a new control module was placed in the unit..still no fix.I had to get back to ABQ so the mechanics reomoved all new parts that they had put on except for the rotors,calipers,and pads.They disabled the ABS unit .I came home and took the Bronco to a very reliable mechanic that I have used.When he removed the wheels he had found that the new rotors that had been placed on in GJ were scared..thus,they were turned..new clapiers and pads were once again placed on the front wheels...bake brakes were checked and they were ok...fluid was once drained and new fluid added.Behold however...they did find the source of the clicking noise...Just prior to going to CO,I had new hubs placed on the Bronco by Desert Rat..I had had the auto hubs changed out to manuals about 6 years ago.Anyway,in replacing the hubs,the mechanic for some unknown reason placed two oil-seals in the hub...thus the noise.Thus,the clicking issue has been resolved,but I have as yet returned to Desert Rat to see what they think of this situtation..Anyway, the ABQ garage did all they could do,and did what the mechanics in CO had done with other parts,and the problem of the ABS has not been resolved.My mechanic called me this PM and asked that I pick the vehicle up tomorrow.They will aslo disable the ABS unit.

There has got to be a solution.4 mechanics who are very famiular with Broncos have not been able to find one. It is a very complex situtation.Who will take the challenge and find the solution? How about you?What is left to check? I've got over $1500 into this problem already....I know that I can use the Bronco without the ABS,but I would appreciate any and all possible solutions and suggestions....Thank you, nmbronco

 

[Tennessee Jed]

I bet a Ford certified dealer mechanic could fix it, one who has been there since the 90's would be best. After all the Bronco is a Truck like the millions of f-150's sold and serviced with the exact ABS system. That will cost you more money.

Some of the folks on this board will have some great answers and I will be looking forward to the knowledge. I have a little overheating problem myself on my 1994 with ABS so I am watching closely.

 

[tres]

I bet a Ford certified dealer mechanic could fix it, one who has been there since the 90's would be best. After all the Bronco is a Truck like the millions of f-150's sold and serviced with the exact ABS system. That will cost you more money.
Some of the folks on this board will have some great answers and I will be looking forward to the knowledge. I have a little overheating problem myself on my 1994 with ABS so I am watching closely.

You may be right.Thanks for your reply,nmbronco

 

[tres]

Tennessee Jed, Thanks for your reply...you just may be on to something with this suggestion.

 

[miesk5]

yo!

Did the mech.(s) give you the ABS Codes they found?

If so, post em here; or get it run thru again or DIY:

4WABS System Component Locations, DTCs & Self Test & Connector Diagram http://www.supermotors.net/vehicles/registry/media/255501_1

Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net

 

[tres]

yo!Did the mech.(s) give you the ABS Codes they found?

If so, post em here; or get it run thru again or DIY:

4WABS System Component Locations, DTCs & Self Test & Connector Diagram http://www.supermotors.net/vehicles/registry/media/255501_1

Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net

Strange..I was told that there were'nt any ABS codes,and that the only code received was a code 16.Man,what a mess! Thanks for your help.

 

[miesk5]

tres,

I was refer. to this section; "...The computer as I understand it was giving readings indicating a problem with the sensors.New sensors where ordered from Denver,and placed on the vehicle...the problem contonues.Had gone to Glenwood Springs,CO for the weekend.Now its Monday.The Bronco was taken to a Napa Shop next door and their computer was giving the same readouts..On Tuesday,a new control module was placed in the unit..still no fix..."

ok, np... do the ABS Code Check yourself or get er done at local shop if you can get it done for free.

pure reasonable guesses for you; some simple (& cheap fixes)

front wheel speed sensor - poor/damaged connection during hub swap...

sensor terminal damage

open/ or shorted sensor circuit.. normal FAILURE

OR REAR RABS Sensor; some call it a vehicle speed sensor) - mounted on rear 8.8 diff;

bad sensor (open or shorted sensor coil; choked with debris and crap

bad connection

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 Circuit 518 (LG/R) or 519 (LG/BK).

defective 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).

some basic RABS Sensor info;

Sensor, VSS or RABS?; by Bronco1 - "Depending on the year; 1992 + - It's called a RABS sensor, or a DSS (diff speed sensor), or rear axle sensor. At work (Ford dealership, we ask for a rear diff speed sensor.

1991 & older - If we want the one on the transmission or transfer case, we ask for the vehicle speed sensor at the trans or tranfercase. "

<a href="http://www.supermotors.net/clubs/superford/vehicles/registry/media/195704" target="_blank">Sensor, VSS (also called called RABS) Location pic in a 95 - rear diff

Source: by Shadofax </a>

RABS Sensor Removal/Installation article & depiction by Chilton via Waltman

Less Likely - Tone Ring (also called Speed Sensor Ring) Inspection in an 8.8 take off the rear diff cover. Check the Ring Tone gear. It is located on the left hand side of the ring gear. Look to see if any of the teeth have been notched (from debris floating around in the diff.) Usually a spider gear. If the ring tone gear has been notched, it will need to be replaced to fix your speedo reading. Jack it up and rotate the tires to look for the teeth to be notched/broken/bent...

Source: by Bighibbi "

GL!

 

[tres]

tres,I was refer. to this section; "...The computer as I understand it was giving readings indicating a problem with the sensors.New sensors where ordered from Denver,and placed on the vehicle...the problem contonues.Had gone to Glenwood Springs,CO for the weekend.Now its Monday.The Bronco was taken to a Napa Shop next door and their computer was giving the same readouts..On Tuesday,a new control module was placed in the unit..still no fix..."

ok, np... do the ABS Code Check yourself or get er done at local shop if you can get it done for free.

pure reasonable guesses for you; some simple (& cheap fixes)

front wheel speed sensor - poor/damaged connection during hub swap...

sensor terminal damage

open/ or shorted sensor circuit.. normal FAILURE

OR REAR RABS Sensor; some call it a vehicle speed sensor) - mounted on rear 8.8 diff;

bad sensor (open or shorted sensor coil; choked with debris and crap

bad connection

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 Circuit 518 (LG/R) or 519 (LG/BK).

defective 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).

some basic RABS Sensor info;

Sensor, VSS or RABS?; by Bronco1 - "Depending on the year; 1992 + - It's called a RABS sensor, or a DSS (diff speed sensor), or rear axle sensor. At work (Ford dealership, we ask for a rear diff speed sensor.

1991 & older - If we want the one on the transmission or transfer case, we ask for the vehicle speed sensor at the trans or tranfercase. "

<a href="http://www.supermotors.net/clubs/superford/vehicles/registry/media/195704" target="_blank">Sensor, VSS (also called called RABS) Location pic in a 95 - rear diff

Source: by Shadofax </a>

RABS Sensor Removal/Installation article & depiction by Chilton via Waltman

Less Likely - Tone Ring (also called Speed Sensor Ring) Inspection in an 8.8 take off the rear diff cover. Check the Ring Tone gear. It is located on the left hand side of the ring gear. Look to see if any of the teeth have been notched (from debris floating around in the diff.) Usually a spider gear. If the ring tone gear has been notched, it will need to be replaced to fix your speedo reading. Jack it up and rotate the tires to look for the teeth to be notched/broken/bent...

Source: by Bighibbi "

GL!

 

[tres]

The shop computer in CO did indicate sensor problems.However,when new sensors ( front and back) were placed on the bronco the problem continued. When I returned to NM the shop in ABQ also replaced the sensors without any luck in fixing the problem.It is interesting to note that the ABQ shop only got a code 16.Please note that before I left CO to come home ,the new sensors that had been placed on the vehicle were removed,the old ones put back on,the ABS system was disabled so that I could make the 345 mile trip back to Albuquerque.The brakes worked fine without the ABS .When I took the vehicle to the ABQ shop,they found that the calipers were not totally releasing thus the need to turn the new rotors that had been placed on the unit in CO.Also ,the ABQ shop put new calipers and pads on the unit.During a test drive it was discovered that the pulsating and pulling problem had not been fixed.Next,the shop put in a new control module...that did not correct the problem so next they put in a rebuilt hydraulic unit which did not fix the problem.It was at this point that they told me that they did not think they could fix the problem.They went online to all ford service manuals they could find on the subject but could not find any further guideance.What a mess.

Now, as I mentioed in the first post,the clicking noise that I was getting when I first discovered a problem was a result of two oil seals having been placed in the left front hub...the ABQ shop found this problem...they guessed the reason for the two oil seals was from the fact the the old seal in the hub was frozen in, and the mechanic was unable to remove it and he placed the 2nd seal over it...or...he had forgotten to remove the original seal and had placed the second seal over the first.At any rate two oil seals where found in the hub.The ABQ shop would not say that this could have created this whole mess.What would you say?

 

[Roadkill]

Just because you have a "Sensor Error" does not nesesarily mean that a sensor is bad. The computer/control module collects information from sensors. If it gets a bad reading, it has no way of knowing if the sensor is bad or if there is another problem causing the bad reading. It only knows that the reading is outside of a set of parameters and sets a trouble code.

You say the problem started after the rotors were replaced the first time. The rotors on your truck are held to the hub by the wheel studs wich are pressed through both pieces (rotor & hub). In order to remove the rotors, the studs must be pressed out of the two pieces towards the rear of the hub. In order for the studs to come out, the ABS tone ring (not sure if that is the proper name for it, but it looks like a gear pressed on the back side of the hub) must be removed from the back of the hub. Assembly is in reverse order with the last step being to press the ring back onto the hub. The ABS system detects wheel movement and speed through the sensor which picks up pulses as the teeth on that ring pass by. If the ring were damaged in any way or not pressed on straight and true, it could cause that wheels sensor to pick up eratic readings. False readings can also cause the computer to set a trouble code and cause the ABS to funtion eraticly.

I am not an expert on ABS (but I am familiar with how the system functions) and this may not be your problem, but I think it is worth checking out.

Edit:

I re-read your initial post and it looks like you say the rotors were replaced by the first shop and then turned at the second shop. It is possible to turn the rotors without removing them from the hub, so the second shop may not have touched the ABS rings (or even looked at them closely). The first shop, however, would have had to remove the rings in order to replace the rotors. If the rings were damaged at the first shop, the second shop could have resurfaced the rotors with out noticing the damage.

 

[miesk5]

Just because you have a "Sensor Error" does not nesesarily mean that a sensor is bad. The computer/control module collects information from sensors. If it gets a bad reading, it has no way of knowing if the sensor is bad or if there is another problem causing the bad reading. It only knows that the reading is outside of a set of parameters and sets a trouble code.
Right! need to get the self test done to get it going on troubleshooting..

You say the problem started after the rotors were replaced the first time. The rotors on your truck are held to the hub by the wheel studs wich are pressed through both pieces (rotor & hub). In order to remove the rotors, the studs must be pressed out of the two pieces towards the rear of the hub. In order for the studs to come out, the ABS tone ring (not sure if that is the proper name for it, but it looks like a gear pressed on the back side of the hub) must be removed from the back of the hub. Assembly is in reverse order with the last step being to press the ring back onto the hub. The ABS system detects wheel movement and speed through the sensor which picks up pulses as the teeth on that ring pass by. If the ring were damaged in any way or not pressed on straight and true, it could cause that wheels sensor to pick up eratic readings. False readings can also cause the computer to set a trouble code and cause the ABS to funtion eraticly.

I am not an expert on ABS (but I am familiar with how the system functions) and this may not be your problem, but I think it is worth checking out.

Right again!

see; 4WABS Sensor, Front Wheel, Removal & Installation in 93-96 Bronco; The front brake anti-lock sensors are attached to the front wheel spindles, and the front brake anti-lock sensor indicators are pressed onto the wheel hub assembly. by combo of Chilton/Nichols/Delmar, & Haynes via autozone.com

somehow, forgot to incl this link last night, was working in a diff location...

4WABS Sensor & Ring, Front Wheel Overview in 93-96 Bronco; The front brake anti-lock sensors are attached to the front wheel spindles, and the front brake anti-lock sensor indicators are pressed onto the wheel hub assembly. The rear brake anti-lock sensors are attached to the rear axle housing. by combo of Chilton/Nichols/Delmar, & Haynes via autozone.com

4WABS Sensor Ring, Front Wheel, Removal & Installation in 93-96 Bronco by combo of Chilton/Nichols/Delmar, & Haynes via autozone.com

4WABS (4-Wheel Anti-lock Brake System) Overview in 93-96 Bronco by combo of Chilton/Nichols/Delmar, & Haynes via autozone.com

Edit:

I re-read your initial post and it looks like you say the rotors were replaced by the first shop and then turned at the second shop. It is possible to turn the rotors without removing them from the hub, so the second shop may not have touched the ABS rings (or even looked at them closely). The first shop, however, would have had to remove the rings in order to replace the rotors. If the rings were damaged at the first shop, the second shop could have resurfaced the rotors with out noticing the damage.

 

[tres]

Yes, the tone rings were removed at the first shop in CO,and replaced when the new rotors were put on the Bronco.I do not recall the second shop(the Abquerque shop) making any mention of the tone rings.All I know at this point and as I have said, I know that the second shop had to turn the new rotors that the first shop had put on.

At this point,I have decided to print out all the replies that have been kindly provided me on this post and will share them with the Albuquerque shop.

I am not mechanically inclined,and I have learned more about Bronco brake systems than I really want to know,but will pass all info on to my mechanic,and am very greatfull to those who have given of their time in helping with this matter.My first Bronco was a new one in 1971...this is the third that I,ve owned..I have enjoyed them.Had lived in the NM mountains for years,and they have gotton me out of some really tight spots.I no longer fish nor hunt,but they were great in getting me around the mountains when I did.

 

[miesk5]

ok, GL with it; the shop should be able to diagnose it w/self test trouble codes..

- now that I have some peace/quiet here, a reacp:

most likely is rear differential ABS sensor (about $21.00 at NAPA, etc.) - sometimes called VSS, rear diff speed sensor, REAR RABS Sensor, DSS (diff speed sensor), Rear Axle Speed Sensor, or rear axle sensor

a pic or 2 by Broncodell in his 95





4WABS Tone Ring, Wheel Bearings, & Warn Hub Swap in a 95

Source: by Trucky18 (B'co) at SuperMotors.net

 

[tres]

Thanks for the pictures.The item shown does not look like the item that the shop in Albuquerque showed to me.If I recall correctly,the front and back sensors looked alike.Could I be wrong about this?

 

[Roadkill]

The front and back sensors are not the same. There two front sensors (one on each wheel) they are shaped different from the rear and the cable is permantly attached to them. They look like this and cost considerably more than the rear one.

Photo is from Partsamerica.

 

[tres]

The front and back sensors are not the same. There two front sensors (one on each wheel) they are shaped different from the rear and the cable is permantly attached to them. They look like this and cost considerably more than the rear one.

Photo is from Partsamerica.

Ok,got the picture...thanks again.I was given the two front sensors as per your pictures.Now I am wondering if they in fact looked at or checked out the rear sensor.I'll have to check with both shops.My! My!