Got these three ABS codes, 42, 52, 54.  Cleared codes and they come back in a few minutes of driving.

 

1999 Subaru legacy sedan automatic 159,000 miles.

 

I'll clean ground wires close to ABS pump and start there.  My guess is that won't fix it though.

 

Brake lights work fine, I checked since bulbs/light issues can cause voltage problems and incidentally trip mulitple codes.

 

The reverse lights weren't working due to a broken wire where the harness pirvots for the trunk opening.  But I repaired that last year and the lights all work as they should.

Check connections in the wire harness plug on the module. I would also pull out the relays and fuses in the module (should be under a black plastic cover) and check those for poor connection as well.

i tried, a little - not much, to track down just what those codes refer to with no success.

 

do you have any drive ability issues?

do you know what the codes refer to?

and of course the most important, done any work recently?

 

what the codes mean may indicate where the problem is but if these are out of the blue i would suspect a connection problem

has it been raining recently?

driven through any deep water?

 

and lastly, if this is your DD, just pull the fuse and be a smart driver.

if it is your wife's, well then ........ good luck and keep at it.

42 low voltage

52 motor relay open circuit/ motor relay ON failure/ abnormal motor

54 abnormal stop light switch

 

I could only find these in the MY96 FSM I have so they may not be the same for 99. I would post details but the diag. trees for these codes are a mile long.

 

Code 42 and 54 seem to indicate a bad connection at the control module, which IIRC is under the passenger seat. Code 52 could be a grounding issue or poor contact at the hydraulic unit and its relay box under the hood, or a poor connection at the control module.

Edited April 26, 201312 yr by Fairtax4me

You might also have had a bit of buzzing coming out of the module?  Almost like the horn is half on?   The wires coming out of the wire harness that bolt to the car body as a ground, near the module.........become corroded after many years.  You need to unbolt the eyelet, wirebrush clean the eyelet, the bracket, the nut and bolt, then slap dielectric grease all around and bolt it back up.  Cured mine.

You might also have had a bit of buzzing coming out of the module?  Almost like the horn is half on?   The wires coming out of the wire harness that bolt to the car body as a ground, near the module.........become corroded after many years.  You need to unbolt the eyelet, wirebrush clean the eyelet, the bracket, the nut and bolt, then slap dielectric grease all around and bolt it back up.  Cured mine.

 

really?  a bad ground definitely cured an issue you had?  sounds easy enough, i've just never had that help anything, start to get skeptical after awhile. LOL

 

i'll clean the grounds in the engine bay then check connectors, then pull the passengers seat.

 

thanks john and fairtax. i'm daily driving it, it drives fine.  when the ABS light is on the ABS doesn't work so no need to pull the fuse, it just defaults to regular brakes. 

 

only work was pulling the engine and the wiring to the rear trunk (sedan).  i've seen some threads where multiple codes (those same 42 and 54) are caused by a bad light bulb screwing with the circuit voltages...but lights work fine and i repaired the wiring....

Edited April 29, 201312 yr by grossgary

ground, no improvement.

 

anyone know for sure where the controller is?   98 and 2000 FSM (i don't have 99) the controller appears integrated into the hydraulic unit.  calls it the ABSC&HU (ABS Controller and Hydraulic Unit) in both.

 

there is a 99 NHTSA and bulletin regarding replacing the ABS controller....maybe that's the deal?

i started a new thread to track down how to find the details of those reports...diagnostics/symptoms maybe. google was scarce.

Edited July 10, 201312 yr by grossgary

When the codes are cleared 52 is the first (and only so far) code to come back, and it comes back immediately.

 

"52 motor relay open circuit/ motor relay ON failure/ abnormal motor"

 

where is the relay for the ABS pump?

 

It doesn't appear on the pump, i unbolted it and disconnected the wiring harness.....didn't see anything.

The relay should be under a black plastic cover on the hydraulic unit.

 

Also since it was mentioned, I said earlier in the thread that the ABSCM is under the passenger seat. That is incorrect. It is in the right corner of the dash next to the glove box.

i'm going to swap out all my brake lights in the rear.  there are threads where someone swapped (working) bulbs and got rid of this code.  easy enough to try.

 

The relay should be under a black plastic cover on the hydraulic unit.

Also since it was mentioned, I said earlier in the thread that the ABSCM is under the passenger seat. That is incorrect. It is in the right corner of the dash next to the glove box.

didn't see anything on hydraulic unit, unbolted it from the car, twisted it all around, disconnected connectors....internal if it's there, have to start unscrewing stuff. who knows but there's no easy access like some of the other ones i've seen.

 

oh no, by the glove box like that impossible to get to door lock timer !(($*($!!!!, i will go without ABS before i torture myself again.  my 96 still has randomly operating door locks because that thing is impossible to get out.  lol  well, maybe a relay is easier.

Yes, the directions for removal instruct to remove two of the bolts that hold the dash assembly and pull the bottom corner of the dash out 5cm. Then it goes on to warn that pulling the dash out more than 6cm may cause damage to the dash.

Of all the things subaru made incredibly easy on these cars, stuff under the dash didnt get out on that list. I think they subbed the dash design out to Honda because they're just as impossible if not more-so.

LOL thanks for saving me the hassle, not worth that, i'm not doing that again!  wow...pull the entire dash for one relay....that's great.  i wouldn't even trust it being there being an oddball one year 99 -with early body style but later gen motor and other stuff.

I've heard of corrosion on the relay causing this issue. I believe there was a TSB on it but cannot confirm as I don't have access to that info anymore. Seen it happen on a few so far.

russ- do you know if the relay is in the hydraulic unit or something? 

The pictures I've seen in the FSMs show a small plastic cover on the hydraulic unit and the relay and several fuses are under that, but I don't think I've seen that section in the 99 FSM. Perhaps it is different on 99 and later cars?

i have seen 99-01 ABS lumped together and other things lead me to think it may be different, but i'm unsure as well.  these 99's are weird with the Phase II engines/trans in earlier bodies.