delco brakes get them working successfully and well

[andydclements]

Andy,

 

I've gone back to basics and I've started re-reading the workshop manual about the ABS, with the rest of this thread to follow. I must have missed something important. I don't have the brake warning light - just the anti-lock warning light. As I understand it, the only component that could be to blame is the part labelled 32 on page Page 1 33.03A in the parts manual, so it's part number A082J6137S. Regardless which part of the switch is to blame, I still need to replace both halves. So I'm stuck for the Australian one you point out, or the Paul Matty version of the same. Two switches in a mounting, replacing one switch assembly. It's true other things like the accumulator could be shot, but the pump runs sensibly for normal amounts of time, and only every 3-5 brake presses. The pressure holds from week to week if I don't drive the car, and the brake warning light isn't on. So I can (and will) do the things you suggest (next week, when there's time, I hope!), but I can't just replace a single switch, can I?

 

Cheers again!

I think that the warning lamp for the low pressure is the same one (left hand side of the binnacle) as that for other ABS related issues, so it doesn't absolutely rule out the other switch, or other ABS problems such as wheel sensor.

[fflyingdog]

Correct.

[TimSportsTourer]

I think that the warning lamp for the low pressure is the same one (left hand side of the binnacle) as that for other ABS related issues, so it doesn't absolutely rule out the other switch, or other ABS problems such as wheel sensor.

 

 

Correct.

 

 

So here are some partial answers (to questions which ultimately are mine, of course). The fault codes that were present before the ABS was cleared after the pressure switch was cleaned up and replaced in situ were:

 

A032 open brake switch or hydraulic leak

 

A042 low brake pressure circuit open

 

A056 test 32 failed

 

The ABS said that these faults have been present for 56 out of the last 56 drive cycles, IIRC.

 

There was no obvious leak of brake fluid, and the reservoir was as expected.

 

I guess these switch-fail codes could have come from a harness failure, so I could try shorting the switch wires, to check that it resets. I could also check the ABS switch on the brake pedal (separate from the brake lights switch, yes? 'Cos the brake lights work fine...) Wheel sensor failures etc would show differently in the ABS memory, so I think I should rule out those issues.

 

Otherwise, it looks like the pressure switch, doesn't it?

 

Sorry to keep banging on about this, but all your help is really good for me, and I am grateful.

Cheers yet again.

[fflyingdog]

I would say its your pressure switch yes

   .You said you cleaned it(pressure switch) did you clean it ultrasonically?  Which would be good if its a mechanical problem, but not much help if the contacts have failed electrically.

[sailorbob]

Those codes are only an indication of the fault(s) last time. You need to find out what code(s) is/are now causing the ABS tell tale to illuminate.

[andydclements]

...A042 low brake pressure circuit open...

Does that mean low pressure on the high pressure switch or low pressure switch?

[sailorbob]

A042 is low pressure (<1800 psi) as indicated by the low pressure switch opening.

 

It's not this again as the brake tell tale is not illuminated.

[rizla603104]

OK guys - so I also have the dreaded flashing light.

 

Can someone give me a list of what I need and where to get it from please?

 

I need a testing kit. So a 4000psi gauge and hose - with I guess a 1/4 flexible EPDM braided hose? How long?

 

I then need the switch kit - from PVL

 

“PSP300 E 1/4P STL” for main switch

“PMN150AE 1/4 STL” for warning light circuit

all fitted with EPDM diaphragms 

 

What connectors do I need? I am guessing M14 to 1/4? - EPDM braided hose - how long should it be - should I get it from PIRTEK?

I then would need 2 x 1/4 T-pieces and connectors - PIRTEK or PVL?

 

I guess you then end up with a long floppy row of switches? What is the best way to keep it all in place?

 

How much should I budget for getting all of this?

 

Apologies for all of these questions

[markw996]

Hi,

 

I haven't done this yet but it is on my to do list.

I did a bit of research about a month ago and this is the parts list I came up with.

 

() MBH14-14 14mm metric male bulkhead with locknut
() BMMF14-14 1/4" BSPP male x 14mm Metric swivel female hydraulic adaptor
() 100STH-04 x 45cm with female 1/4" BSPP ends
() BEVT14-14-14 1/4" BSPP male/female/male tee hydraulic adaptor – swivel female on branch
() BTF14-14-14 1/4" BSP female/female/female swivel female equal tee hydraulic adaptor
() 4000PSI 1/4" BSPP Gauge

() PMN 150 A W E R14 (1800PSI is 124BAR)
() PSP 300 W E R14 (2700PSI is 186BAR & 2400PSI is 165BAR)

 

A also made a diagram in Excel to help me understand what I needed (and to stop me wasting money on bits I didn't need) which I have attached. Good luck as this will be a project I will be doing around March next year when my Esprit comes out of hibernation

 

Regards,

Mark.

DIY ABS Connectors.xls

[andydclements]

That's a lot less then £300, so for areas that don't need type-approval, a great way round it.

[rizla603104]

Looks like a great list! Thanks - that is really helpful.

what about copper washers - what size will I need? Can you let me know what size AMP connector I will need to? I would like to leave the wiring loom as it and just connect on the new switch assembly. Is there anything else?

Edited October 20, 2013 by rizla603104

[sanj]

I need a testing kit. So a 4000psi gauge and hose - with I guess a 1/4 flexible EPDM braided hose? How long?

 

You can find original test gauges on eBay fairly cheap. Search for Kent-Moore J-37118. Here's one:

http://www.ebay.com/itm/300979355228

[markw996]

You can find original test gauges on eBay fairly cheap. Search for Kent-Moore J-37118. Here's one:

http://www.ebay.com/itm/300979355228

 

Thanks for the info, I just bought a similar one on eBay.

£41 delivered from the USA   

[markw996]

Incidentally, if anyone is interested I bought a new accumulator from the USA for less than £90 delivered.

 

http://www.ebay.co.uk/itm/390667120353

 

(1 still available)

 

HTH 

Edited October 22, 2013 by markw996

[wohlmeyer]

I finally got my car down off the stands and used it for the first time Monday. Have to say it wasn't great, not so much the actual feel of the pedal, just the fact that the pump relay was tripping continuously most of the journey every time the brake pedal was applied.

 

It was the same on the journey home from work, so the car is off the road again for investigation. I have considered things it could be and have two possible causes. The accumulator which I think is the problem, or the management system of the abs. I've fitted one of Steve's switch conversions so have ruled that out. I've videoed the car and the abs unit so you can see what's happening to mine.

 

http://youtu.be/s1QT3wFpN0M

 

I'm going to get a new accumulator and take it from there. You can hear it starts alright, the light has gone out at this time correctly. I'm applying the pedal and it's operating the accumulator pump every second go, which is too often, also the light is on by now and flashing. You can see the master cylinder moving as I apply the brake.

OwenGT3, this is EXACTLY what my S4S is doing right now.  What was your final solution?

 

Thanks

Bill

[andydclements]

Owen has fitted the two-part switch replacement which has separate standard hydraulic switches, one to do the pump (high pressure) and one to do the warning light (low pressure switch). Own has also fitted a pressure gauge to enable the adjustable switches to be set accurately, and replaced the accumulator. You may be able to guess that I've spent quite a bit of time helping him on it.

[wohlmeyer]

Okay.  So it was not a malfunctioning relay as he originally thought?  It was that cursed pressure switch...Early on he had mentioned that he purchased a switch from LotusMarques.  Did that switch malfunction?  What was wrong with the LotusMarques switch?  I have heard others say that the LotusMarques switch worked great.  This is the first I have heard of it not working.

 

Bill

Edited November 23, 2013 by ramjet

[andydclements]

After a fair bit of work with that switch arrangement, we found that there was a setting issue. Having become rather despondent we resorted to testing the on/ off function and found that the pump switch was only just operating above the pressure that the warning light switch was operating. Initially we guessed that it would mean that the warning switch was set too high, so adjusted it down to approx 2/3 of the other. Once Owen managed to make up some more plumbing and get a gauge, it was found that the high pressure switch was set to circa 1500 instead of 2500, had that high pressure one been right, it may well have worked as designed first time round.

Owen tried fitting a new accumulator, both on its own and with the new switches but with the high pressure switch set too low, it resulted in worse operation. Once the high pressure switch was adjusted up to 2500 and the new accumulator fitted things have improved dramatically.

[ramjet]

Andy, I thought that Steve supplied the switches already set to the correct pressures? If it should have come already set correctly, I highly recommend letting Steve know as he would definitely like to know that something slipped through. He really is a professional like that.

[andydclements]

Hi. Steve does know and replaced the switch that was assumed to be faulty. It may have been set incorrectly, perhaps even set to the same point as the other switch or even altered in transit. 

[OwenGT3]

Hi, Thanks Andy for providing information regarding my ABS issues. As Andy has said, my abs is now working correctly and all the time I've made adjustments to the switches I purchased from Steve, I have informed him of my results and progress. Steve knows about the calibration of the switches and that the settings were wrong for my car, I stress my car as the factory setting may work on another car.

 

I think Steve is considering providing the switch set up he sells with the ability to plumb in a gauge, that was mentioned in my last correspondence, which is key to setting up any switch replacement you fit substituting the original switch. I Fitted a 3000 psi pressure gauge purchased from eBay for £8. I then took the whole switch set up to a hydraulic company and got the fittings to plumb in the gauge and switches.

 

I had to make just one part, which was to allow two different thread to come together. I had to weld two unions together to make one. This is my set up now.

 

 

I have also fitted a new accumulator, which I purchased from the USA. I found once the gauge was fitted it highlighted that the pre-charge pressure was only just about the recommended replacement figure of 500 psi. The new accumulator hits 1000 psi straight away. I've also disconnected the abs as it used to cut in at too low a speed, I now prefer it with out the abs in operation, give me a nice firm pedal.

 

What ever set up you fit to your car to replace the old switch, it will never be a complete substitute for the old. Even though mine works OK most of the time, occasionally you may have the light come on again, I've had it happen once so far. Fitting non genuine parts, switches that have not been tested to work in the cars abs set up, so issues may arise from time to time. What helps is I know the system is working again and well, so if the light does come on, then it's not a major problem, it usually clears on the next start up of the car, it's to be expected for a make do and mend to sorting the switch problem.

 

What is important is do fit the gauge, you cannot set up the system without it.

 

You will have to play about with the setting of the switches as well, it won't come first time and don't do it just on a partly charged system. Check the system pressure form no charge to see how the pressure climbs and settles. You need to check on the way up and the way down regarding the pressure, this way you will find the ideal spot for the adjustment screw.

 

Remember to plumb in the gauge equal or before the switches to get a better reading.

 

 

Edited December 14, 2013 by OwenGT3

[Bibs]

A PH'ers suggested solution! 

 

http://www.pistonheads.com/gassing/topic.asp?h=0&f=17&t=1370675&i=999999&nmt=ABS%20Light%20is%20on.%20.%20.98%20GT3

 

 

Is that not illegal somehow?

[Mike6]

Did that myself after MOT man said seatbelt light didnt come on when ignition switched so an MOT failure. Came home fiddled around with no luck so disconnected another warning light and plugged it into the seat belt slot and bingo MOT pass a couple of house later. Got home and switched bulbs back again. Must remember to do same again at next MOT.

[andydclements]

A PH'ers suggested solution! 

 

http://www.pistonheads.com/gassing/topic.asp?h=0&f=17&t=1370675&i=999999&nmt=ABS%20Light%20is%20on.%20.%20.98%20GT3

 

ABS Light is on. . .98 GT3 - PistonHeads.clipular.png

 

Is that not illegal somehow?

Not really, as long as the car is still roadworthy. It;s not a legal requirement to have ABS, so as long as it fails safe (when it fails you don't loose braking control) then you're really just back to assisted braking only.

[TimSportsTourer]

Not really, as long as the car is still roadworthy. It;s not a legal requirement to have ABS, so as long as it fails safe (when it fails you don't loose braking control) then you're really just back to assisted braking only.

 

Actually, I'm not sure this is true. When I had my last MOT, I was told that they check in the computer to see what the test for a particular car is meant to entail. If your car had ABS when it was built, it is on the list to be checked. From observation at the test, I've no reason to believe otherwise. It's just as well I managed to get the ABS working again, as I too had blithely assumed I could strip it out and ignore it, but this is not so.

 

There's a book on the .gov.uk website here that describes the MOT test. On the subject of brakes, it says:

 

Brakes: Condition including inappropriate repairs or modifications, operation and performance (efficiency test). Note the removal of the road wheels and trims are not part of the test. Anti-lock Braking System (ABS) and Electronic Stability Control (ESC) where fitted. Check of the dashboard Malfunction Indicator Lamp (MIL) for ABS, ESC, electronic park brake and brake fluid warning.

 

So part of the check includes that the ABS light illuminates, and goes off, usually after three seconds, I think. What I can't remember is if they check the ABS operation on the rollers, or on a road test, whichever they choose to do. It could be that it's in the roller check, but for mine, the chap opted for a road test, worrying that the splitter would hit the ground under braking when on the rollers, and he may well have been right. Of course, he did get to drive the car, which might have been another factor in his choice. I couldn't say. The road test involved him using an accelerometer to check the car slowed appropriately. It did, it seems.

 

It may be that you can tell the DVLA that you have removed the ABS, just like you can tell them you have changed the colour of your car, but I don't know that this is the case. I do believe that by default, they expect that if it had ABS when it was new, it still has a working ABS function.

 

I did consider making a tiny PCB with a timer chip on it to turn the light off after 3 seconds, but I decided against it, and luckily, managed to get the ABS fixed with expending sums of money that were too vast. Phew. And actually, the brakes are working pretty well now, after a small modicum of fettling.