Ford Truck Fanatics  



Home Gallery TOTM New Posts My Threads / My Replies Links Sponsors Calendar Arcade Calculators Fliers
Go Back   Ford Truck Fanatics > F-Series > Generations 8-9

Generations 8-9 1987-1996 F150 + 1987-1997 F250, F350

Reply
 
Thread Tools Display Modes
  #1  
Old 05-22-2020, 10:30 PM
Kaajot Kaajot is offline
Micro Machine Manager
 
Join Date: Jul 2014
Location: Bumblebee's Junkyard
Posts: 233
Kaajot is an unknown quantity at this point
Question Rear ABS Illuminates -- will not produce fault code at test

Hello-

I've checked multiple sources, videos, searches and have a good enough understanding on how to check my ABS when Rear ABS illuminates. The Brake light is not illuminating, reservoir is full. I replaced the Speed Sensor at the rear axle last August to fix up its fault code. No fault code for it now.

However, if I'm driving and get about 40-45 mph, maybe 35 mph occasionally, the Rear ABS light illuminates solid and does not go out. The truck feels like a boat and is very unstable in this as well. Now I know I need to do my right tie rod (have a new one, just waiting to get a non-bent rim for that tire and to do it all at once), but that pull was evident months ago and now the Rear ABS is causing a whole different danger zone of slop (I do not drive fast nor far with the truck at this point yet again).

Here's the kicker. I have tried to pull the code 2 through 16 by grounding (after key on) the ABS II style tester. It's under the glove box, and supposedly it's supposed to have memory too if it's the ABS II. I've tried every grounding to steel, negative battery ground and direct to negative battery. I cleaned the ABS II pin and tried going behind just in case to make better contact with the wire, but I'm not able to get codes for the Rear ABS Fault. I drove and triggered the fault, kept the engine running, and tried grounding the tester and still no code just in case it was acting like an ABS I and would wipe the codes upon power off to the truck.

Any ideas? I feel like it could be my Speed Sensor went bad, but I should be getting a computer code too. Since I get a fault triggered but I cannot get the fault code, I'm leaning towards the Rear ABS Module behind the glove box being bad? I mean, it's 27-28 years old so.... maybe?

Anyone ever had a problem pulling the Rear ABS fault code test? Solutions? Common causes?

Thanks.

-KJ
__________________
1992 F-150 Custom "Red IX"
1991 F-250 302 5.0 Plowtruck Project
1983 F-700 10K Dump Truck, no CLD Req'd :-)

"Not too impressed.... often."
Reply With Quote
Sponsored Links
  #2  
Old 05-23-2020, 07:50 AM
Kaajot Kaajot is offline
Micro Machine Manager
 
Join Date: Jul 2014
Location: Bumblebee's Junkyard
Posts: 233
Kaajot is an unknown quantity at this point
Finally found a RABS test — not even in my Hanes manual — regarding illuminated but no code given when performing RABS test. Initial instinct was right — looks like I’ll be opening up the glove box to get my RABS module number and find a new one.

https://www.f150online.com/forums/wh...ing-light.html
__________________
1992 F-150 Custom "Red IX"
1991 F-250 302 5.0 Plowtruck Project
1983 F-700 10K Dump Truck, no CLD Req'd :-)

"Not too impressed.... often."
Reply With Quote
  #3  
Old 05-23-2020, 09:05 AM
Fellro's Avatar
Fellro Fellro is offline
Ford Truck Fanatic Administrator

Moderator
Admin
 
Join Date: Jan 2007
Location: Iowa County, Iowa
Posts: 7,601
Fellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond repute
You shouldn't notice any difference in how it drives just becasue the ABS is out, it only pulses the the brake to prevent brake lockup. It does not apply pressure when you don't. I actually only backs off the pressure, not apply. Basically, when ABS is non-functional, your brakes will behave as normal. One thing I have found before is that the physical abs control can fail and will actually block pressure from getting to the rear brakes. On that truck I just removed the entire ABS system. We also are not subject to safety insppections, but there are times the vehicle will be safer without the damn ABS.
__________________
My trucks:
The workhorse, 86 F250 4x4 6.9 nat aspirated, 3.25 exhaust, custom intake, electric fuel pump, otherwise well used stock... not real pretty but just loves to work!

The other heavy hauler, 92 F350 2wd dually crew cab, flatbed/toolboxes, 92 Cummins VE 12V with intercooler, NV4500 manual

The beater: 88 F250 4x4, 5.8 5 speed
The project ... 1978 F150 4wd shortbed 351 auto

ASE certified parts specialist
I do most all of my own work so I know who to complain to..Roger
Reply With Quote
  #4  
Old 05-23-2020, 09:33 AM
Kaajot Kaajot is offline
Micro Machine Manager
 
Join Date: Jul 2014
Location: Bumblebee's Junkyard
Posts: 233
Kaajot is an unknown quantity at this point
Quote:
Originally Posted by Fellro View Post
You shouldn't notice any difference in how it drives just becasue the ABS is out, it only pulses the the brake to prevent brake lockup. It does not apply pressure when you don't. I actually only backs off the pressure, not apply. Basically, when ABS is non-functional, your brakes will behave as normal. One thing I have found before is that the physical abs control can fail and will actually block pressure from getting to the rear brakes. On that truck I just removed the entire ABS system. We also are not subject to safety insppections, but there are times the vehicle will be safer without the damn ABS.
So, I know my right-pull when hitting an abnormality in the road was my tie rod, which is evidence from the front right wearing down despite replacing the tie rod 2-3 times (and drag links and bearings etc etc) because the Rim is likely bent/warped, and I'm going to get a new rim, new set of front ties, and then fix all of it.

But why when the R ABS light came on did my driving go to crap? I know my braking seems slower, but no visible leaks or loss of brake fluid. It feels very much like a boat right now since the light came on.

I guess the worst thing I can do is continue pulling the module out to get its number and see how it runs? Will removing the module short the system into default driving, or is there more to it to elmination?

MI Plates on the truck so no inspections but if I put NYS plates it'll be a problem (I think I only get out of emissions part of the test due to age of truck).
__________________
1992 F-150 Custom "Red IX"
1991 F-250 302 5.0 Plowtruck Project
1983 F-700 10K Dump Truck, no CLD Req'd :-)

"Not too impressed.... often."
Reply With Quote
  #5  
Old 05-23-2020, 10:59 AM
Fellro's Avatar
Fellro Fellro is offline
Ford Truck Fanatic Administrator

Moderator
Admin
 
Join Date: Jan 2007
Location: Iowa County, Iowa
Posts: 7,601
Fellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond repute
Might simply unplug the module and see, otherwise check for brake drag. I suppose it could be possible to have the brakes holding pressure with a failed actuator. Kind of like when a brake hose fails internally and holds pressure.
__________________
My trucks:
The workhorse, 86 F250 4x4 6.9 nat aspirated, 3.25 exhaust, custom intake, electric fuel pump, otherwise well used stock... not real pretty but just loves to work!

The other heavy hauler, 92 F350 2wd dually crew cab, flatbed/toolboxes, 92 Cummins VE 12V with intercooler, NV4500 manual

The beater: 88 F250 4x4, 5.8 5 speed
The project ... 1978 F150 4wd shortbed 351 auto

ASE certified parts specialist
I do most all of my own work so I know who to complain to..Roger
Reply With Quote
  #6  
Old 05-23-2020, 05:06 PM
Blue-Truck-Nut97's Avatar
Blue-Truck-Nut97 Blue-Truck-Nut97 is offline
 
Join Date: Oct 2019
Posts: 466
Blue-Truck-Nut97 is a splendid one to beholdBlue-Truck-Nut97 is a splendid one to beholdBlue-Truck-Nut97 is a splendid one to beholdBlue-Truck-Nut97 is a splendid one to beholdBlue-Truck-Nut97 is a splendid one to beholdBlue-Truck-Nut97 is a splendid one to behold
Quote:
Originally Posted by Fellro View Post
You shouldn't notice any difference in how it drives just becasue the ABS is out, it only pulses the the brake to prevent brake lockup. It does not apply pressure when you don't. I actually only backs off the pressure, not apply. Basically, when ABS is non-functional, your brakes will behave as normal. One thing I have found before is that the physical abs control can fail and will actually block pressure from getting to the rear brakes. On that truck I just removed the entire ABS system. We also are not subject to safety insppections, but there are times the vehicle will be safer without the damn ABS.
Just adding to your statement here, if it blocked pressure to the rears, thus doing all the stopping with the front, combined with loose steering, bad tie rods, bent wheel and who knows what else at this point, sure could account for bad handling in my opinion.

Sent from my E6810 using Tapatalk
Reply With Quote
  #7  
Old 05-23-2020, 08:45 PM
Kaajot Kaajot is offline
Micro Machine Manager
 
Join Date: Jul 2014
Location: Bumblebee's Junkyard
Posts: 233
Kaajot is an unknown quantity at this point
Quote:
Originally Posted by Blue-Truck-Nut97 View Post
Just adding to your statement here, if it blocked pressure to the rears, thus doing all the stopping with the front, combined with loose steering, bad tie rods, bent wheel and who knows what else at this point, sure could account for bad handling in my opinion.

Sent from my E6810 using Tapatalk
Yeah, what you and Fellro makes sense. The back differential and drums were rebuilt ~4.5 years ago. New lines, so that's why they're not busted, but maybe something is blocked back there.

I'm getting to the module first thing in the morning tomorrow, soldering in a new pig tail to the distributor (finally) and then servicing one more generator and my spare lawn mower. (Got 2 Champion Generators, Weed Whipper, and Mower serviced plus flag pole rebuilt and up and repainted and the new Saab wheels Chromed and mounted finally, so moving along here). Truck's about to get some attention and then when DMV/SOS opens up F-150 will go in for that engine servicing -- towing 1K gallons of water to the farm so I can manage the animals while it's getting diagnostics and hopefully that head job done.

Oh, one other thing -- I threw a new Neutral Safety Switch in last month and unfortunately fixing the pins may have bungled up the reverse lights sensor AND it's now actually requiring a little jockeying to start -- think I have the alignment off, but also know I stripped frayed the pins trying to add a new terminal cap, gave up and put the old one back on. Unsure if the NSS wiring communicates much with the ABS module -- I do know it is infact responsible for my reverse lights not firing unless I jockey the driving switch between Reverse and Park and lift up just a little to make the contact realize I'm in Reverse and need those lights on.

That's on my radar but again, I don't think it's the main factor in the Rear ABS going very off. It does feel like there's some drag once the light illuminates and it does feel like the front brakes are doing most of the work -- I think they have for awhile actually. I'm going to guess it's a bad module (will find out, probably a fried capacitor or burnt trans path) and the blocked rear pressure.
__________________
1992 F-150 Custom "Red IX"
1991 F-250 302 5.0 Plowtruck Project
1983 F-700 10K Dump Truck, no CLD Req'd :-)

"Not too impressed.... often."

Last edited by Kaajot; 05-23-2020 at 09:17 PM. Reason: Gals, not Lbs. Tiered. ^_^
Reply With Quote
  #8  
Old 05-24-2020, 08:52 AM
Fellro's Avatar
Fellro Fellro is offline
Ford Truck Fanatic Administrator

Moderator
Admin
 
Join Date: Jan 2007
Location: Iowa County, Iowa
Posts: 7,601
Fellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond repute
If it is blocked, and related to the abs, it will be the actuator that is located below the master cylinder on the frame up front. I removed that on the 92 when it was only working the front brakes. Bad deal on a truck that regularly tows in excess of 10,000 pounds.

https://www.rockauto.com/info/1/122024-rit__ra_p.jpg
__________________
My trucks:
The workhorse, 86 F250 4x4 6.9 nat aspirated, 3.25 exhaust, custom intake, electric fuel pump, otherwise well used stock... not real pretty but just loves to work!

The other heavy hauler, 92 F350 2wd dually crew cab, flatbed/toolboxes, 92 Cummins VE 12V with intercooler, NV4500 manual

The beater: 88 F250 4x4, 5.8 5 speed
The project ... 1978 F150 4wd shortbed 351 auto

ASE certified parts specialist
I do most all of my own work so I know who to complain to..Roger

Last edited by Fellro; 05-24-2020 at 08:56 AM.
Reply With Quote
  #9  
Old 05-24-2020, 11:34 AM
Kaajot Kaajot is offline
Micro Machine Manager
 
Join Date: Jul 2014
Location: Bumblebee's Junkyard
Posts: 233
Kaajot is an unknown quantity at this point
Quote:
Originally Posted by Fellro View Post
If it is blocked, and related to the abs, it will be the actuator that is located below the master cylinder on the frame up front. I removed that on the 92 when it was only working the front brakes. Bad deal on a truck that regularly tows in excess of 10,000 pounds.

https://www.rockauto.com/info/1/122024-rit__ra_p.jpg
Found it for my unit too -- should be easy enough. Will I have to bleed brakes? I've got a manual, if the process is there I can read it.

Did you eliminate it though? Or upgrade?

I don't do 10K lb loads often (once maybe?) but 2K - 6K is not infrequent, every few months. I've already upgraded the Suspension to F250 in the back, springs, etc. Some day I plan on upgrading the front controls to F250/350 bearings to accept that kind of work more regularly. The Spring Coils up there are already upgraded, but I think I run through wheel bearings too fast due to the loads I exceed (legally, way beyond GVW, etc). Although the more I think about it, the more I think the blockage may have been in the back for a long time. I've been wearing through my front brakes, calipers, rotors, etc everything up front way too often and my former mechanic (he's out of business) never thought much of it.... so, maybe this ABS thing really is the fundamental problem to my way-too-frequent bearings, tie rods, etc that I've replaced since 2015.

The first 6 years they were fine, then transmission blew and well, too many fires on one vehicle and I think not enough SA by mechanics to really get a grasp of all the problems at once.






Not Related: Forgot, when I did the Neutral Safety Switch swap to a 1995 upgrade (better rain seal to keep moisture out) I also redid the wiring from the amp to the starter solenoid. New, heavy duty inline fuse and beautiful wiring done properly and housed securely out of the way of heat and oil. That fixed some more of my alternator fluctuations and now it's just needing some tweaks to the tensioner and power steering pump to likely keep the belt from any slipping that causes erratic amp fluctuations when turning slowly in low gear. No overcharging of battery or anything else and the amp stopped failing again, so the wiring was a big step in the right direction of getting rid of grounding and shorting issues on that power line.
__________________
1992 F-150 Custom "Red IX"
1991 F-250 302 5.0 Plowtruck Project
1983 F-700 10K Dump Truck, no CLD Req'd :-)

"Not too impressed.... often."
Reply With Quote
  #10  
Old 05-24-2020, 11:42 AM
Fellro's Avatar
Fellro Fellro is offline
Ford Truck Fanatic Administrator

Moderator
Admin
 
Join Date: Jan 2007
Location: Iowa County, Iowa
Posts: 7,601
Fellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond reputeFellro has a reputation beyond repute
I simply removed and bypassed the actuator. Yes, you have to bleed out the rear brakes no matter whether you replace or bypass the actuator. The F350 it was on tows big round hay bales, horse trailers, and other such things regularly.

Regarding the NSS, I do agree it seems out of adjustment.
__________________
My trucks:
The workhorse, 86 F250 4x4 6.9 nat aspirated, 3.25 exhaust, custom intake, electric fuel pump, otherwise well used stock... not real pretty but just loves to work!

The other heavy hauler, 92 F350 2wd dually crew cab, flatbed/toolboxes, 92 Cummins VE 12V with intercooler, NV4500 manual

The beater: 88 F250 4x4, 5.8 5 speed
The project ... 1978 F150 4wd shortbed 351 auto

ASE certified parts specialist
I do most all of my own work so I know who to complain to..Roger

Last edited by Fellro; 05-24-2020 at 11:51 AM.
Reply With Quote
Reply

Tags
abs, fault codes, rear abs

Thread Tools
Display Modes

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

Forum Jump


All times are GMT -5. The time now is 01:43 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Ford Truck Fanatics is not affiliated with or endorsed by Ford Motor Company.