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98 Amigo antilock

32K views 58 replies 6 participants last post by  alanb21 
#1 ·
The antilock warning light on my 98 Amigo is on most of the time. A friend of mine has a code reader which indicated ALL antilock codes being set. He was not able to reset codes. Any ideas?
 
#52 ·
OK, I'm stumped....today I used a magnet to test each of the solenoid cores inside the hydraulic block. They each respond to the magnet just fine. You can hear a faint 'snap' of the valve inside when the magnet is placed close to the exposed nipples seen on the front of the block. Each one was tested separately, and repeatedly, the top row has a more faint sound than the bottom row, but all work. I also tested the motor by applying 12v directly to the motor leads and it runs as expected. Draws about 5.5 amps. So what is the deal?

I compared the 'cores' response to a closely placed magnet on both the used unit and my original unit. Very similar results on both. I checked the ohms of the used unit motor (2.5 ohms) and my motor ( .5 ohms) and thought that might be a problem. But, they both run just fine with 12v applied and draw about the same amount of amps. One thing to note, the motor can be removed from the back of the hydraulic block without losing brake fluid. The motor shaft moves a couple of 'plungers' that appear to be spring loaded on opposite sides of the motor shaft. I couldn't see anything obvious about the motor shaft that makes the plungers move though.

I decided to remove the battery cable and see if that would 'reset' the captured code in the ABS system. left it disconnected 1 and 1/2 hours. Nope, no difference; ABS light still on when power was restored and the key was placed in the ON position. Drove the Trooper, light stayed on. Parked, shut her down, restarted later, light still comes on. I'm ticked off.

Driving home I decided to jam the brake pedal fast and hard to see if the ABS kicked in (pulsating brake pedal). Nope. Tried it a second time.....same response.

What I haven't done is check to see if the same 43 code is stored. I'll try to check that out tomorrow.

Time for J Lemond or a miracle......
 
#53 ·
Yesterday I drove the Trooper around town running usual errands etc. The ABS light stayed on each time it started up and while driving around making several stops. When I got home I decided to stop at the mailbox and check the mail. I switched the Trooper off to do that, walked to the box, took maybe 15 seconds, came back to the Trooper and restarted it. ABS light came on as usual on startup, then went OFF......stayed off until I got to the garage, about 40 seconds ( I was getting excited ) then came back ON as I drove into the garage. Dang!

I decided to check the codes by jumpering 5 and 12 again.....got the same code 43. Dang it !!
 
#54 ·
Does anyone have a diagram of the pinout of the main connector that attaches to the ECBM ? Today I was going to do some checks on the ABS again but I don't have the details needed on the connector. I need to know which is pin #1 thru the last pin.
I also noted today that I got a 35 code when jumpering 5 and 12. In the past I had gotten a 43 code. So something has changed. Any ideas ? I had pulled the 40A circuit breaker and F9 a couple of weeks ago, but put them back in just before checking for codes today.
 
#57 · (Edited by Moderator)
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Thanks Buster. This would be looking at the main connector C4 turned upside down after removing from the EBCM. I finally figured out the pinouts with the help of some materials JLEMOND sent me. Great stuff!!
I think I finally broke my unit by poking around on the wires that go to the circuit board inside. I now get 2 codes...43, and 44. I noticed yesterday that 2 of the tiny wires were broken free from their pads. I tried to solder them back, but not so lucky. This is delicate stuff to deal with.
I think I'm gonna cut wire #16 and see if that puts the ABS light out on the dash.

Some other info that may help others. If you look at the pics I've posted of the circuit board, you'll see the 3 sets of larger wires coming to the boards edge. Those are the signals going out to the Orange solenoid coils. The Blue solenoid coils share a common 'leg', not sure if its ground. I think it goes to the 'swinger' of a relay, but can't confirm that. I don't have schematics of the circuit to verify my suspicions. I couldn't trace out the other sides.....my ohmmeter started acting up on me.

The pump motor (I'll post pics) has a offset shaft that alternately pushes plungers on opposite sides of the motor shaft to move brake fluid thru the block. The 'C' ring inside the block holds the plungers together so the move in the same direction at the same time. Simple but effective. The pump motor gets 12vdc via its separate connector from the EBCM when needed.
 

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#58 ·
FINAL note on this........unable to get the electronics to work so I called in JLEMOND for help. Just removing the fuses didn't put the ABS light out, unplugging the large main connector from the electronics didn't put it out either. Per JLEMOND the yellow #16 wire had to be cut to do the trick. He was right!! As usual. No more ABS light on the dash panel now.
 
#59 ·
This isn't really a reply to a previous post but I thought that I could add this since the subject is the same. I now have another 98 Amigo. This one has the 6 cylinder engine. It also has the abs warning light on. Since I have a relatively new HCU sitting in the 4 cylinder unit, I tried switching them. The light went out and stayed out during my test drive until I was a few blocks away from home. Hard key produced codes 12 (start), 51, 61, 52 and 62 in that order. I have not performed any other tests yet.
Thanks in advance for any replies,
Alan
P.S. The 4 cylinder Amigo abs light is now on also.
 
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