ABS Module Bench Test? Is it possible?

Burttj03

Burttj03

Joined
Apr 19, 2021
Messages
28
Age
31
Location
53511
Hello all,

I am currently trying to figure out the issue with the ABS on my dad's 2003 ST1300A. The ABS light has been constantly flashing (even with the bike not running, but the key turned on). I should mention that the LED for the ABS light had been desoldered from the PCB by a previous owner, so I'm assuming this issue has been around for awhile and someone tried to hide it...

It wasn't until I took apart the dash to see if the ABS LED had failed that I realized it was missing. Thankfully, though, when I sent the dash into Bluegauges to have the colors changed he soldered a new one onto the PCB.

Now, the LED is functional, but it is constantly blinking (when the key is turned to the on position, and the bike is either running OR off). I tried erasing the code, and that worked, but only until I had run the bike again--upon which the code then returned. So, obviously there is a fault with something in the system. Additionally, I purposely tried to lock up the brakes to see if the ABS was in fact non-functional, and sure enough the rear wheel locked up and skid, so I think I'm safe in assuming that it's not working. Also, just this week I bled the entire braking system following @jfheath article guide, along with so many other helpful tips throughout this forum, and I am confident that the brakes are working optimally (other than the ABS)--the PO we purchased this from had just replaced the SMC as well, and it is functioning properly. The brakes are working great other than the ABS not working! No weird dragging, noises, vibrations, etc.

When I retrieved the code, it was code 12. According to the manual, possible faulty components include: front modulator fuse, front modulator motor, ABS control module, or wiring harness.

Well, I've checked all of the ABS related fuses and they are fine; I've done a lot of other work to this recently, so I have been doing my best to inspect the entire wiring harness as I go, and clean/regrese (properly, with the proper dielectric grease) each connector that I have been able to see; and the front modulator and it's connectors all appear fine. I also replaced both the front headlight subharness, and FI subharness (that contains the knock sensor connectors, etc.) with a good condition harness, and a new harness, respectively.

So, I'm starting to think it's the ABS control module. Fortunately, I have found some tested replacements on ebay, and I may purchase one if it is in fact that part causing the issue.

However, before I do that, does anyone know if there is a way to bench test the ABS control module? I've searched up and down through this forum, and the manual, and haven't been able to find any information on if it's possible to test it.

Thanks for your help in advance!
 
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I have several ST1100 ABSII models, and I have never seen a 'bench test' for their ABS control. So I would be surprised if there is one for the ST1300 ABS. About all you have is the 'flashing light' sequence to try to determine the issue. Make sure that all your grounds and hots (frame and battery) are clean and secure. I know on the ST1100 ABSII that battery/connection/ground issues will cause the ABS system to throw errors.
 
I have a working ABS unit on my work bench if needed.
I also have a couple other ideas for you to check.
Standing by the white courtesy phone if needed.
 
Uncle Phil said:
I have several ST1100 ABSII models, and I have never seen a 'bench test' for their ABS control. So I would be surprised if there is one for the ST1300 ABS. About all you have is the 'flashing light' sequence to try to determine the issue. Make sure that all your grounds and hots (frame and battery) are clean and secure. I know on the ST1100 ABSII that battery/connection/ground issues will cause the ABS system to throw errors.
Click to expand...

Thanks for the tips! Thanks to the copious amounts of incredible information on this forum, I've read all about the issues that have popped up on numerous ST's with the the yellow ground block in the subharness by the headlight, the two blocks (the yellow power block, and the pink-ish ground block) located underneath the PAIR solenoid, the main ground point under the upper tank, etc.

When we first picked up this bike, I removed all of the fairings, and saw that the front yellow ground block by the headlights had been chopped into and "repaired".... Moreover, I saw that both wires that lead to the knock sensors on each side were in rough shape and starting to crack and corrode. Furthermore, I noticed that a PO had removed both ends of the solo green ground wire that runs through the 24 pin connector on the left side of the bike, cut the pins off, and soldered a new wire to each end of the green wire outside of the connector (I know that the ground wire burning through this 24pin connector was a somewhat common problem). Well, I didn't really like the quality of all of these "repairs".... So, this lead me to getting a lightly-used front headlight subharness, a new FI subharness (for the knock sensors/coolant temp sensor ground/etc.), and resoldering/sealing/taping a new wire between the solo green ground wire at the 24 pin connector where I also soldered/sealed/taped a 16awg "tee" wire that splices off of the newly connected ground wire and routes/connects to the clutch pipe bracket (with adhesive lined marine shrink tubing over a high-heat ring terminal) that is located near the 24pin connector/ignition connector/etc. as an additional grounding point.

This particular bike being an '03, it has had the ground cap recall done for the original ground block that is located under the PAIR solenoid (as well as all of the other recalls done), but I still opened that recall-modified ground block--as well as the other two--and completely cleaned them/checked for damage/regreased them/wrapped them securely with silicone repair tape, and high-heat Tesa Tape over that (51036). I also took the advice of others on this forum and removed the brass jumper from the (now "lightly used") front headlight yellow ground block, cleaned it, and soldered a 16awg wire to the top of it, then routed that to a proper grounding point where it was connected with a sealed ring terminal, and then taped the whole wire run with Tesa Tape.

As I've gone through this wiring, I thoroughly cleaned every wire connector and grounding point in the frame (both the terminals, and the actual bolt and threads where they connect) that I could get my hands on with QD electronic cleaner, compressed air, a little terminal file and/or a brush connected to my drill on low speeds (where appropriate), and regreased and reconnected each connector. I taped every part of each wiring harness that I could get to with Tesa tape in hopes of adding further protection to the wires for years to come--including all of the wires at the main grounding point under the upper tank that thankfully had not been chafed through yet! To be sure that all of the grounding points were quality, I tested for both continuity (with the battery disconnected) and voltage (while connected), and thankfully they all read 0 resistance/strong continuity, and read battery voltage. So, I feel that all of the grounding points are now very strong and secure.

As I've been working through the bike, I would say that I've been able to visually inspect most of the main harness (I had a lot of the bike disassembled in order to do this) and the subharnesses, and thankfully there was no apparent damage anywhere other than what I already mentioned!

All in all, I feel confident that I've solved any issues that may have been present with the wiring by utilizing a combination of proper sealed solder and crimp connections, dielectric grease, silicone repair tape (where necessary), and plenty of Tesa tape/zipties.

Lastly, I just got a brand new battery yesterday. I fully charged it, popped it in, and erased the ABS codes once more. Well, unfortunately, after turning the key off and then back on, the code returned--and this time there was a second new code (Code 13).

I'm definitely now thinking that it is the ABS control module. I see that the manual states in the troubleshooting guide that if, after erasing the codes, the light starts blinking again and it displays code(s) 12 and/or 13, then it's a faulty ABS control module. So, that's where I'm now at. @Igofar, I will message you my number and talk to you soon, and hopefully we can figure this out!

Thank you all for your help!!
 
That sounds like an extensive, detailed and thorough quality control process.
Also sounds like 2 or 3 days' work.
How long did that take, not counting the deplasticking time?
 
Sadlsor said:
That sounds like an extensive, detailed and thorough quality control process.
Also sounds like 2 or 3 days' work.
How long did that take, not counting the deplasticking time?
Click to expand...

Thanks! I've been doing my best to be as thorough as possible with each step on this bike!

As far as timeline, it's been somewhat all over the place. Until this May, my dad previously had a very nice 1999 Honda Shadow Ace Tourer VT1100T that I had done some work to. While that was an excellent motorcycle in it's own right, he was just looking to get something a bit more powerful and long distance touring-capable. My brother has an 2008 FJR1300, and I have a 2006 V-Strom DL1000, (both of which I've done a lot of work to) so I started researching sometime last year about potential alternatives to my dad's Ace Tourer. From everything that he said he wanted in a bike, the ST1300 seemed to fill every desire. So, I started reading about them as much as I could in this forum, the other ST forums, the manual, YouTube, etc. I have spent a concerning amount of my free time over the last year or so reading threads on this forum from years and years ago before we even got the ST, Lol! So, I was somewhat primed to the great aspects, and the potential issues, that come with the ST before we actually found a great deal on a used '03 this past April.

We picked up the bike this past April, and I immediately began working on it in hopes of having it all done relatively quick so that we could all ride together this summer/fall. Well, with the combination of my OCD, certain parts being backordered and having to wait a LONG time for them to become available, and with the shipping delays related to COVID, it's definitely taken a lot longer than I had hoped it would. But, you know what, I feel really good about the fact that the bike will be restored to a proper motorcycle once again, and hopefully last a very long time issue-free! Honestly, aside from the engine itself, for the most part the only remaining "wear items" that haven't been replaced will be the SE Thermal (wax) valve, the swingarm bearings/seals, and the u-joint/boot--all of which are fine as of now. Also, I haven't done the counter-balancer adjustment yet, but may do that soon.

I've replaced all wheel/flange/steering head(replaced with tapered) bearings and seals with quality NTN bearings and OEM seals; installed all new coolant lines and joints with new o-rings (OEM) and quality German made spring clamps from Belmetric (on every single line except the two ends of the radiator hoses in fear of crushing them, so I just cleaned and reused the OEM clamps at those two barbs) and made a brass tee to replace the plastic one that many have said will eventually fail that connects to Hoses A, C, and B in manifold if I remember correctly; installed a new thermostat and oring; fully rebuilt the water pump assembly and installed a new oring; installed all new OEM fuel lines and sealing washers; installed all new vacuum lines (OEM for PAIR hoses and some others, Belmetric for TB's and some elsewhere) and cleaned both five way tees; did a valve adjustment (most exhaust valves were a little tight) and replaced both cylinder head gaskets, as well as the oring gaskets for the spark plugs that sit beneath the cam journal covers, and all of the copper sealing washers; did a starter valve sync/cleaned and lubed all of the started valve and wax valve shafts with dry Teflon lube; installed a new air filter; went through and fixed all of the wiring/installed wolo bad boy horn and a high amp rated powersocket--both with waterproof relays and 12awg wiring; installed symtec heated grips on top of the stock grips and then placed new grip puppies over that; cleaned and added new moly paste loctite lb8012 (yes, I read the entire Moly thread.... Hahaha) and new o-rings on the flange and hub splines; mounted and balanced new tires; installed new pads and did a complete brake system flush; installed a new fuel pump (denso 951-0004 thanks to @Mellow 's recommendation of filing down the connector to fit into the bikes stock connector) and high pressure fuel filter/OEM submersible fuel lines/metal mesh filter/sock/rubber boot/rubber packing gasket/sealing washers for new fuel feed line; new Barnett kevlar clutch plates (steel and friction) and springs; installed a new clutch slave cylinder assembly (OEM) and oil seal (OEM) that sits in the recess inside of the slave cylinder, and new sealing washers on the banjo bolts; rebuilt the front forks with new bushings, seals, dust seals, and fork oil--and I read and followed the collective advice of the manual, @dduelin, @jfheath, and @Igofar regarding front end alignment and combined all of it when I reassembled the front; installed new OEM throttle cables and G2 Ergonomics throttle tube and adjusted properly; and lastly installed a new AGM battery. There may be more that I'm forgetting, lol.

The only darn issues that remain are the ABS that I mentioned, and the windscreen motor gear and cables being stripped and chewed up.... But, I have an idea for the screen that I'm going to try this winter to fix it--for now, it will stay up and installed so my dad can actually ride it during these last couple riding months here in Wisconsin!

I've done tons of reading on this forum, and in the manual, and watched many videos on YouTube as I've worked on this bike over the last 5 months, and I now feel like I am very familiar with this motorcycle. I just want to say a truly sincere thank you to all of you on this forum who have chipped in fantastic advice over the years--it's allowed me to complete every step that I've done thus far with confidence!! And, after test driving this bike a few times over the last week or so, I now have the urge to get one.... Haha!
 
Well, thought I'd update everyone with some news regarding the ABS issue. I was going to try to order a module off of eBay, but I actually ended up finding a guy that was relatively local to me (about two hours away) who had a few working used modules, and he agreed to let my dad and I ride down, pop one in, and test it out to see if it fixed the problem.

Once we got there, I disconnected the battery, popped out the old unit, popped in the new one, reconnected the battery, started the bike/test drove it, and BINGO! All is well and working now! The ABS light now functions as it should with the light being solid upon turning the key/starting the bike, and the light turning off once a speed of roughly 6mph is reached.

So, it was the control module after all. It's very weird to me why these issues with the modules have popped up with various owners over the years. Especially with the modules being wax potted to prevent vibrations destroying them and whatnot! It makes me curious if it is a hardware issue with a component on the circuit board failing, or maybe a software/firmware issue? Just very strange to see that bad ABS modules have been a somewhat common occurrence for many owners.

I was recently reading about similar issues with the PGM FI Controller (ECM) and how some older units start to display Code 25 and/or Code 26 regarding the left/right knock sensor(s), and most owners experiencing that issue found that it was a bad ECM throwing those codes. The ECM is also wax potted, and I just find it strange and unfortunate that these issues have arisen for many people with both units.

Just want to thank everyone for the help and guidance--espscially @Igofar for calling me, and talking with me for hours about different things regarding the ST1300, etc.
 
Burttj03 said:
So, it was the control module after all. It's very weird to me why these issues with the modules have popped up with various owners over the years. Especially with the modules being wax potted to prevent vibrations destroying them and whatnot! It makes me curious if it is a hardware issue with a component on the circuit board failing, or maybe a software/firmware issue? Just very strange to see that bad ABS modules have been a somewhat common occurrence for many owners.
Click to expand...
Older ABS control modules on cars had what I think is the same issue. The soldered joint to the ABS pump develop a poor connection. You can find ABS module repairs on Youtube where the cut the module open and resolder the joints. Usually with a pump fault code you can verify the pump working by jumping it. Bmws had problems with the ABS pump brush holder rusting and the pump fails. That fix is a bit more complicated but cheaper that a $2500 unit.
 
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