Bushwack Posted February 15, 2013 Share Posted February 15, 2013 Car: A 1989 Coupe.Problem starting twelve days ago: ABS light came on after getting the car washed on two separate occasions. ABS light turned off each time about 5 minutes later never to reappear until yesterday.Problem as of yesterday: After the car has been warmed up and driven a few minutes (i.e. at idle at a red light, stuck in freeway traffic or cruising at 65MPH), the ABS light comes on. Sometimes it will stay on until I shut the car down. Other times it will flicker and other times it will come on for a minute and then go off, come on again for a minute and then off again (whether or not I apply the brakes).Yesterday, with the ABS light already on for a couple minutes, the brake light came on while cruising on the freeway. Having just changed both the accumulator and brake fluid a couple weeks ago (200 miles ago), I'm dismissing these two items as being the cause. With both ABS and brake light on (and then the CRT telling me I have low brake pressure even though the brakes felt fine), I pulled off the freeway and parked the car. With the engine idling, I popped the hood and there was no visual indication of a problem (and nothing leaking on the ground). I shut off the engine, waited a minute, turned the ignition back on and neither light appeared. I was able to get back on the freeway and travel another 28 miles without neither light coming back on.My gut tells me I have an electrical issue. Either a loose sensor (maybe a bad sensor) or a ground problem. I took the brake pump test that was suggested three weeks ago from this thread (http://forums.aaca.org/f116/1989-reatta-cant-identify-sound-343874.html) and the accumulator solved that problem. Is there anything else electrical related I should look at (fuse...relay??)? From past experiences, reading ABS codes can be misleading; especially when it comes to the wheel sensors. I'd appreciate any suggestions/advice. Link to comment Share on other sites More sharing options...
Ronnie Posted February 15, 2013 Share Posted February 15, 2013 When the red light comes, for some reason the pump is shutting down momentarily. When the red light comes on due to low pressure the yellow light will always be on. A number of things can cause the pump to stop. Accumulator is not one of them. Link to comment Share on other sites More sharing options...
padgett Posted February 15, 2013 Share Posted February 15, 2013 There is a level sensor in the resovoir - check the wiring to that. Did the CRT say low LEVEL or low PRESSURE ? All of that said there is a procedure in section 5e of the service manual on how to pull brake codes (jumper a-g (88) or a-h (89) andturn ign on, count abs flashes - will be number, pause, number, longer pause then next code if more than one. Link to comment Share on other sites More sharing options...
DAVES89 Posted February 15, 2013 Share Posted February 15, 2013 The red light could be as simple as your emergency brake being "tripped" just a bit. Or as you stated that you just changed your brake fluid it could be that your brake fluid is just a bit low. Check to make sure the fluid is correct once again. If you are not sure just add about 1 ounce. However if you have noticed anything different [brake pedal appearing hard]about your brakes you should get them checked. Regarding the yellow light coming on intermittently especially after a car wash, I would hazard a guess that you have a frayed brake sensor lead that shorts out due to the water and then dries out. Most likely the front. If it is only frayed and still works it could still be saved by an application of a product called "Plasti Dip" which is applied with a foam brush. It was a product tried by Padgett and used by me on a number of leads. It is non toxic and easy to use. Of course if you would rather replace the lead I would be happy to take the "suspect" lead off your hands. Link to comment Share on other sites More sharing options...
Bushwack Posted February 16, 2013 Author Share Posted February 16, 2013 There is a level sensor in the resovoir - check the wiring to that. Did the CRT say low LEVEL or low PRESSURE ? All of that said there is a procedure in section 5e of the service manual on how to pull brake codes (jumper a-g (88) or a-h (89) andturn ign on, count abs flashes - will be number, pause, number, longer pause then next code if more than one.The CRT said low pressure. I will look at the ABS codes but I don't place much faith in them for as I mentioned, they can be wrong. Had not thought about the sensor in the reservoir. Link to comment Share on other sites More sharing options...
Bushwack Posted February 16, 2013 Author Share Posted February 16, 2013 The red light could be as simple as your emergency brake being "tripped" just a bit. Or as you stated that you just changed your brake fluid it could be that your brake fluid is just a bit low. Check to make sure the fluid is correct once again. If you are not sure just add about 1 ounce. However if you have noticed anything different [brake pedal appearing hard]about your brakes you should get them checked. Regarding the yellow light coming on intermittently especially after a car wash, I would hazard a guess that you have a frayed brake sensor lead that shorts out due to the water and then dries out. Most likely the front. If it is only frayed and still works it could still be saved by an application of a product called "Plasti Dip" which is applied with a foam brush. It was a product tried by Padgett and used by me on a number of leads. It is non toxic and easy to use. Of course if you would rather replace the lead I would be happy to take the "suspect" lead off your hands.I will check the parking brake. Brake fluid is OK (I'm fortunate to have more then one Reatta to use as reference for these kind of issues). It's at the same level if I was to pump the brake 30 times w/o the ignition on and if the car was warm (I duplicated this procedure on the other car). The frayed sensor is along what I am thinking. I have an extra set to use but I was thinking, as I'll have new shocks/struts installed in a couple weeks, to have the mechanic detach then re-attach the original sensors; looking if there are any hints of an cosmetic issue. If the problem comes back, I'll replace the sensors. But would a bad sensor trip the red brake warning light?One more thing that may/may not be an issue. I did have the battery replaced before the car received its first car wash (and appearance of the first ABS light sighting). Not sure if that could be the root of the problem (I assume not). Link to comment Share on other sites More sharing options...
DAVES89 Posted February 16, 2013 Share Posted February 16, 2013 Detaching and reattaching isn't like doing the battery to "reset" everything. I would take your extra set of sensor leads along to the shop when you do your struts and have them ready should your mechanic determine if your existing ones are bad/frayed. He should use an ohm meter to check your new leads verses the leads existing on the car. Then swap any that give you a bad reading. Link to comment Share on other sites More sharing options...
SeanR Posted February 16, 2013 Share Posted February 16, 2013 Does the ABS remain off while parked and running? It would seem that after reaching 5-15mph, one of the wheel sensors is triggering a code. If it's never moved, would like to know if light never appears. Link to comment Share on other sites More sharing options...
Ronnie Posted February 16, 2013 Share Posted February 16, 2013 Car: A 1989 Coupe.... the brake light came on while cruising on the freeway. Having just changed both the accumulator and brake fluid a couple weeks ago (200 miles ago), I'm dismissing these two items as being the cause. With both ABS and brake light on (and then the CRT telling me I have low brake pressure...I may have gave the right answer to the wrong question. The problem quoted above, (that to me means the pressure in the system is too low), is what my previous comments were based on. Wheel sensor testing or replacing is not going to cure a RED brake light when a low pressure warning is being displayed. As I've said before, you must fix the problems causing a Red brake warning light before you tackle the problems causing a Yellow ABS light. Link to comment Share on other sites More sharing options...
Bushwack Posted February 17, 2013 Author Share Posted February 17, 2013 I haven't yet taken on the suggestions previously posted but to add a bit to what has just happened.Last night I drove 70 care free miles. No problems. This morning I drove (back home) 70 miles. About 7 miles from home and on the freeway, without having applied the brake pedal for at least the past 20 miles (if not more), the ABS light came on with the brake light to follow about 5 seconds later and thereafter the CRT telling me I have low brake pressure.Is the ABS pump or any part of the braking system doing anything while cruising (and the brakes not applied)? I would think no which leads me thinking having an electrical (or sensor) problem. I did cautiously drive home (5 of the last 7 miles is city driving) without a problem and without any noticeable difference on applying the brakes or with stopping. Link to comment Share on other sites More sharing options...
Ronnie Posted February 17, 2013 Share Posted February 17, 2013 (edited) The pressure in the brake system will bleed down over time even in a perfectly operating system, even if you don't apply the brakes. That is the reason the brake pump runs when you first turn on the key after that car has been sitting for an extended period. Assuming you went 20-30 minutes without touching the brakes, that might be long enough for the reserve pressure in the accumulator to drop low enough that the pump would need to come on and build the pressure back up in the system. If for some reason the pump didn't come on due to a failing pressure switch, bad brake pump relay or even a problem with the motor (like a bad place on the armature) it could account for the red brake light coming on. If you haven't already done so you should replace the brake pump relay just to ensure it isn't the cause of the problem. Cheap insurance against future problems. Edited February 17, 2013 by Ronnie (see edit history) Link to comment Share on other sites More sharing options...
Bushwack Posted February 19, 2013 Author Share Posted February 19, 2013 (edited) There is a level sensor in the resovoir - check the wiring to that. Did the CRT say low LEVEL or low PRESSURE ? All of that said there is a procedure in section 5e of the service manual on how to pull brake codes (jumper a-g (88) or a-h (89) andturn ign on, count abs flashes - will be number, pause, number, longer pause then next code if more than one.This morning I took an ABS reading (twice). The first code was 22 (LF inlet valve) and the second code was 48 (3 sensors). No other codes came up (or should I say blinked). What puzzles me further is after taking the readings, I let the car warm up, depressed the brake pedal 25 times once temperature was at 182 degrees, then went on my way to work; making sure I came across every speed bump and stop sign. Neither the ABS or brake light came on.I'm not sure what the next step is regarding code 22 but I'm hesitant regarding any code dealing with wheel sensors as we know the diagnosis isn't always correct. Suggestions?? Postscript: 4 hours later leaving the office, both ABS and brake light came on upon start up. I let the engine warm to an idle, then popped the hood and gave all four connections a jiggle to see if they were secure (which they felt to be but they all had some 'play'). When doing so, my passenger said the red brake light went off (and stayed off for the 25 minute drive to my destination - ABS light stayed on).Does someone know what each module does (yellow, red, blue and green?) Also, which of the three relays on the firewall is for the ABS? I assume it's #3 (I can't find reference to this in the fsm).Thanks.... Edited February 20, 2013 by Bushwack (see edit history) Link to comment Share on other sites More sharing options...
wws944 Posted February 20, 2013 Share Posted February 20, 2013 Ervin - from what I've seen, you must take the wheels off to examine the ABS sensor leads. The point where the sensor leads tend to break is a couple of inches up from the wheel hubs. Especially the ones on the front wheels. Link to comment Share on other sites More sharing options...
Bushwack Posted February 23, 2013 Author Share Posted February 23, 2013 A couple days have passed and the ABS and Brake light come on intermittently (often the ABS light will come on 8..10 minutes into driving). I'm not convinced yet the problem is the ABS wheel sensors only because the light doesn't immediately come on and stay on. Going back to the two pictures I posted a couple days ago in this thread, I know when I jiggle these modules (sensors?) before I start the car, the red brake light will stay off and usually so will the ABS light (but it does eventually come on while driving). If I don't give these four sensors a jiggle before ignition, the red brake light will come one. In this mode, while I haven't simulated a panic stop, the brakes feel and work the same with or without the ABS and/or Brake light on.Assuming I have exhausted all other possibilities, I will reluctantly change out all four sensors next week (while I have the shocks/struts replaced). But I wouldn't mind understand the TEVES system further; especially what the 4 circled items do.I know the yellow circled item in the picture is the sensor for the brake reservoir. Can someone tell me specifically what the red, blue and green circled items do? Also, is it #2 or #3 that is the brake pump relay? Link to comment Share on other sites More sharing options...
Guest crazytrain2 Posted February 23, 2013 Share Posted February 23, 2013 (edited) green= 12V power supply connection to motorblue= Pressure switch connectionred= Main valve connectionyellow= Brake fluid level sensor connection Edited February 23, 2013 by crazytrain2 Relay pic (see edit history) Link to comment Share on other sites More sharing options...
padgett Posted February 25, 2013 Share Posted February 25, 2013 That you have an ABS code is significant, check all leads. The EBCM mayl not trip a code until the car is moving above a certain speed for a certain time. Any time the red light is on (and not the parking brake) it will turn off the ABS which turns on the yellow light. Have to deal with the red light first.If stymied I have been know to run test leads from thing like to pump power line to a light by the dash so I know when the pump runs. If light is out and you get a low pressure signal check the wiring/switch. If on and you get it, check the pump. Link to comment Share on other sites More sharing options...
Bushwack Posted February 25, 2013 Author Share Posted February 25, 2013 This brake system is possessed. Drove the car all day on errands. Turned the car on and off 3 times over a 55 mile drive. Neither ABS or brake light turned on...until the 4th time. ABS and brake light on upon start up until I got home.I bypassed the A & H after the 1st trip to see what codes I'd get. None. Zippo - no codes came up (ABS didn't blink at all). Should of took another reading when I got home but I was exhausted. Tomorrow is I will change the brake pump relay as Ronnie suggested and see how the devil behaves.. Link to comment Share on other sites More sharing options...
wws944 Posted February 25, 2013 Share Posted February 25, 2013 I still maintain that before you start replacing parts, you should pull the front wheels and carefully check the sensor leads for cracks. Link to comment Share on other sites More sharing options...
Guest crazytrain2 Posted February 25, 2013 Share Posted February 25, 2013 When red and yellow lights are on does the brake pedal become "hard"? If so you might try disconnecting the plug going to pressure switch (blue), look closely for any sign of brake fluid inside the connector. If present, switch is bad and needs replaced. Link to comment Share on other sites More sharing options...
Bushwack Posted February 25, 2013 Author Share Posted February 25, 2013 Changing the brake pump relay isn't difficult. Aside from trying a panic stop, the brakes work/feel the same whether one or both lights are on. Was hoping to change the relay today but life got in the way. Maybe tomorrow.Walter - leads will be looked at and/or changed either way later this week when I put shocks/struts on.Speaking of wheel speed sensors, do they just fail (like a non-rechargeable battery) or can they be repaired? I would think cracked wires can be repaired but do the sensors themselves fail? Link to comment Share on other sites More sharing options...
DarrenG Posted December 27, 2016 Share Posted December 27, 2016 (edited) Bushwack, Did you ever resolve this issue? My wife has an 89 Reatta that I had up on stands in the garage for a few years as I rebuilt the trans and the engine. Before it was put up on stands there was no problem with the ABS now the ABS light is on all of the time I have checked everything as per the manual I get no codes, no red brake light, all fuses and relays are good, brakes bled, grounds have been cleaned and have good continuity, wheel sensors test good, pump builds pressure from what I can tell everything is working correctly so I am not sure why the ABS light is still on? Darren Edited December 27, 2016 by DarrenG spelling (see edit history) Link to comment Share on other sites More sharing options...
padgett Posted December 27, 2016 Share Posted December 27, 2016 Wha code is it giving ? Have to wonder if with it on stands and the suspension dropped to max if you didn't stretch a sensor cable. Link to comment Share on other sites More sharing options...
DarrenG Posted December 27, 2016 Share Posted December 27, 2016 Hi, No Codes. The front suspension was removed and rebuilt with OEM parts a complete rebuild and one lead was replaced I purchased it from DAVE89 ohm tested all of the leads and they are good. I have been trouble shooting this for months without success. Drove the car above 25 MPH and still the ABS light from hell?????? Link to comment Share on other sites More sharing options...
zoltanb Posted January 2, 2017 Share Posted January 2, 2017 If you have a pin-out box for the abs computer in the trunk you can check the system, if not may I suggest trying another computer. 1 Link to comment Share on other sites More sharing options...
DarrenG Posted August 29, 2018 Share Posted August 29, 2018 Hi I tried a computer that I got from the wreckers and I fixed the problem. Thank for all of the help. Link to comment Share on other sites More sharing options...
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