Abs Diag Wiring (306/205 Hybrid)

[brian j 32]

I have replaced the ABS on the 205 with the Bosch 5 system from 1998 306.

 

Having put it together the ABS light is still on.

 

I have checked and double checked the wiring and it all seems to be OK, the sensors are in the resistance spec and show a good trace on a scope, but the ABS light will not go out (It hasn't since the unit was fitted.)

 

I am having trouble getting the fault diagnosed, because the car does not have an OBD port. (Currently I have a 2 pin JPT socket with the Diag and ABS light lines in) Does anyone have a wiring diagram for which lines go to which wires on the OBD port so I can get one wired up and read a fault code?

 

Thanks.

[welshpug 1,646]

the 2 pin JPT plug is the diagnostics port, no need to fit the DL16 plug, most obd readers wont do ABS faults, all you need is the switch and light bulb type readers like you'd use on the earlier engine ecu's.

 

check that it powers up properly, not unknown for the relays to fail which will bring the light on, or rather not extinguish it when ignition is turned on.

 

 

I had no luck whatsoever extracting any fault codes from my ZX's Bosch system, neither did my local specialist who has the period and up to date readers.

 

all it was in the end was a sensor

[pug_ham 243 3 Cars]

The diagram below is from autodata.

 

 

Have you got the brake pedal position switch in place (S13)?

 

Looking at the diagram it has an input to the ecu.

 

g

[welshpug 1,646]

that's just the brake light switch, there isn't a second switch

[pug_ham 243 3 Cars]

Yeah but it has an input to the abs ecu so has Brian done this?

 

g

[brian j 32]

Yeah but it has an input to the abs ecu so has Brian done this?

 

g

 

Yes,

 

I have piggy-backed a feed from the existing brake light switch, so that it goes 12v+ when the brake pedal is pressed. I also have the two 12v lives fused through the shunt box, 2 earths to the inner wing, switched live and abs light on the original 205 connector (It's easier when the car always had ABS) and obviously the ABS sensors. I'm running Xsara trailing arms and zx volcane ABS CV joints to get the right number of teeth on the front ABS rings.

 

The only thing I think that I'm lacking is the OBD port connection, because the Bosch 5 ABS doesn't support flash codes and I need to get someone with a code reader to link it up and read what's wrong with it.

 

I know I could just wire the two pins from my diag plug through, if I knew what the OBD port pinout was.

 

Oh, and thanks for the diagram Graham. :-)

[pug_ham 243 3 Cars]

The only thing I think that I'm lacking is the OBD port connection, because the Bosch 5 ABS doesn't support flash codes and I need to get someone with a code reader to link it up and read what's wrong with it.

 

I know I could just wire the two pins from my diag plug through, if I knew what the OBD port pinout was.

 

I'll have a look at my autodata & se if that gives any help with regards to the obd port & post any pictures etc I find that might help.

 

g

[pug_ham 243 3 Cars]

Just started looking through autodata & noticed this note at the top of the warning lamp circuit info page;

 

ECU harness multi-plug may contain a switch function so that, if disconnected, the warnign lamp(s) will illuminate.

 

Also for when you get any codes here's the list of them from autodata;

 

 

It doesn't show a breakdown of the odb socket wiring though unfortunately.

 

g

[brian j 32]

Just started looking through autodata & noticed this note at the top of the warning lamp circuit info page;

 

ECU harness multi-plug may contain a switch function so that, if disconnected, the warnign lamp(s) will illuminate.

 

Also for when you get any codes here's the list of them from autodata;

 

 

It doesn't show a breakdown of the odb socket wiring though unfortunately.

 

g

 

Thanks Graham! :-)

 

Does anyone else know the OBD socket pinout on a 1997 306?

[Miles 331 1 Cars]

They don't have one unless it's a phase 2, even then the ABS I'm sure does not connect into it

[welshpug 1,646]

97 306 would be bendix IIRC not bosch, bosch was a very early system.

[pug_ham 243 3 Cars]

97 306 would be bendix IIRC not bosch, bosch was a very early system.

Brian says in his first post it's from a 1998 306 so I was looking at the later Bosch 5.3 system for 97> 306's not the <96 Bosch 5.0.

 

g

[brian j 32]

Brian says in his first post it's from a 1998 306 so I was looking at the later Bosch 5.3 system for 97> 306's not the <96 Bosch 5.0.

 

g

 

It is from a 1998, Ph2 Xsi. It is externally identical to the Bosch 5.3 in my Ph3 306 HDI. The car did have a load compensator on the rear beam though, so I believed it to be a Bosch 5.0 system. Furhter research says it is indeed a Bosch 5.3. Sorry for any confusion.

 

If it helps, the Bosch part number is 9625242180

 

Also, by Ph2, I am informed everywhere I check that the diagnostics were wired through to an OBD style connector under the dash.

 

I really want to find a way of getting fault codes out of this before I have to go and buy another abs unit...

 

Thanks

[welshpug 1,646]

You'd need some Peugeot specific diagnostic kit seeing as its pre 2002, confused me by saying it had a JPT plug though, if it has that surely it'll do the flash codes like the ecu's? (not that it ever bloody works!)

Edited January 9, 2012 by welshpug

[ade 4wd 11]

Bosch 5.3 ABS, check the following connections on ABS unit.

 

Wheel sensors-

1+2 RR

8+9 RL

5+3 FR

6+7 FL

 

21 warning lamp

17+18 constant 12V

15 switched 12V

14 brake switch input

16+19 earth

 

11 diagnostic line connects to pin 12 on 16 pin OBD.

 

NOTE- some Bosch 5.3 units use 5+4 for the FR wheel sensor.

[brian j 32]

Bosch 5.3 ABS, check the following connections on ABS unit.

 

Wheel sensors-

1+2 RR

8+9 RL

5+3 FR

6+7 FL

 

21 warning lamp

17+18 constant 12V

15 switched 12V

14 brake switch input

16+19 earth

 

11 diagnostic line connects to pin 12 on 16 pin OBD.

 

NOTE- some Bosch 5.3 units use 5+4 for the FR wheel sensor.

 

Thank you. That's a big help. I assume the "OBD" port needs a power and earth. You don't know the pins for that too do you? If I have the signal on pin 12, power, and earth should I anything else to allow a pug-specific scanner to read it?

[ade 4wd 11]

To read ABS fault codes from 16 pin OBD connect as follows -

 

1 switched 12V

4+5 earth

16 12V

12 ABS diag line

 

Thats all the connections you will need to read ABS fault codes. A peugeot specific fault code reader will be required as its pre 2001 and not OBD complient.

[brian j 32]

Thanks all for your help.

 

IT WORKS!!!!!!!!!!!

 

Found the dreaded bosch 5.3 ABS module was faulty. Bought another from a breakers, fitted it today and the ABS light is out!

 

MOT booked for tomorrow and then, when my hands have recovered and my wife lets me near it with spanners, (she's been patient and there are things needing done in the house!) the valve stem oilseals can be changed and the Motronic 3.1 conversion can start.

Edited January 12, 2012 by brian j

[pug_ham 243 3 Cars]

Nice one brian, at least you got there in the end.

 

Good luck with the MOT, the MP3.1 can be done in a weekend.

 

g

[Tom Fenton 1,536]

Good work, this is something I have toyed with the idea of doing.

 

Now you have got it functioning properly, how does it actually work, by this I mean when you stamp on the brakes, how good is it at stopping the wheels locking but still slowing you down in a reasonable time?

[brian j 32]

Good work, this is something I have toyed with the idea of doing.

 

Now you have got it functioning properly, how does it actually work, by this I mean when you stamp on the brakes, how good is it at stopping the wheels locking but still slowing you down in a reasonable time?

 

TBH,I need to get out of traffic somewhere to try it (not easy in my part of London),so it'll be a few days till I can have a go, but I'll feed back what I find ASAP.

Edited January 15, 2012 by brian j

[brian j 32]

Ok. The results are in.

Last night thoughtfully provided Damp greasy roads and quiet traffic so I have done some testing.

 

I'm happy. The abs cuts in pretty much identically to my 306 and keeps the wheels from locking while keeping the tyres just lightly squealing. The feel and positivity of the brakes is also better by far than the original 205 abs, although its way too long since I drove a non-abs 205 to compare.

 

All in all I think it was a very worthwhile job and recommended for a road car IMHO.