[928uk] ABS fault 87 S4 auto

[Vince Dallimore]

Hi simon, 

I’ll test again with the spanner tomorrow, when I refit the ECUs. 

Regards, 

Vince Dallimore 
M: +44(0)7798 630649

Sent from my mobile

87 S4 auto; 88 S4 manual; 86 S2 (barn find) 

TIPEC Regional Organiser; North London, Herts & South Essex

E: NLHSE at TIPEC.net | W: www.TIPEC.net
Membership - T: 01787 249295 | E: membership at tipec.lpl-uk.com | W: www.tipec.lpl-uk.com
 
Follow us on twitter   @porsche_tipec

> On 29 Jul 2022, at 19:49, Simon Painter <simonpainter101 at gmail.com> wrote:
> 
> All measurements taken from the ABS plug; all sensors measure in spec.
> 
> Measured for +12v on pin 1 and only measured 10v. Swapped the relay with a spare and then it read +11v! I then removed relay and fitted a jumper to provide permanent +12v, which then measured fine at pin 1. However, fault still present. 
> 
> I also checked and bench tested both relays on the actual ABS pump - both fine. Also checked the +12v power feed to the pump and that was fine too. 
> 
> I ran through the Bosch Hammer before I started investigating the ABS so can’t remember if it actually detected and tested the ABS ECU.
> 
> Something for for Vince to try next......
> 
> Thanks
> 
> Simon.
> Check me out on Instagram @oldcarfixer
> 
>> On 29 Jul 2022, at 19:08, Paul Lacey <t595 at btinternet.com> wrote:
>> 
>> Hi Vince,
>> Have you tested all four sensors to the ABS ECU plug ?
>> 
>> Regards,
>> Paul L
>> 
>> -----Original Message-----
>> From: Vince Dallimore [mailto:vm.dallimore at gmail.com] 
>> Sent: 29 July 2022 18:49
>> To: 928UK List
>> Subject: Re: [928uk] ABS fault 87 S4 auto
>> 
>> Hi all,
>> 
>> I had a new abs sensor fitted by Loe bank at service; this cleared the intermittent fault I’d experienced for years. 
>> 
>> After returning to London and using the car whilst the manual went for service, the fault light is now on from engine start? 
>> 
>> The JDS Spanner shows no faults, sensors all show good readings; the relays all function and no wiring issues found. Today the ABS ECU was swapped for the one from my manual, but no change in the permanent fault light, so it’s not the ECU. 
>> 
>> Any thoughts on what could cause this “untraceable” fault; could it be an issue with the central warning system? 
>> 
>> Hoping there’s some thing I and Simon Painter have missed!
>> 
>> Regards, 
>> 
>> Vince Dallimore 
>> M: +44(0)7798 630649
>> 
>> Sent from my mobile
>> 
>> 87 S4 auto; 88 S4 manual; 86 S2 (barn find) 
>> 
>> TIPEC Regional Organiser; North London, Herts & South Essex
>> 
>> E: NLHSE at TIPEC.net | W: www.TIPEC.net
>> Membership - T: 01787 249295 | E: membership at tipec.lpl-uk.com | W: www.tipec.lpl-uk.com
>> 
>> Follow us on twitter   @porsche_tipec
>> 
>>>> On 29 Jul 2022, at 18:36, Adrian Langford via 928uk <928uk at lists.928.org.uk> wrote:
>>> 
>>> I thought the one on which I carried out an autopsy was sealed. At any rate it was a devil of a job to get inside!
>>> 
>>> It was originally installed on my 1991 S4, where the WOT switch had failed. New one has been fine in the three years since.
>>> 
>>> Adrian
>>> 
>>>> On 29 Jul 2022, at 11:09, Jonathan Rackowe via 928uk <928uk at lists.928.org.uk> wrote:
>>>> 
>>>> Has anyone ever known of one of the replacement Bosch sealed Throttle
>>>> Position Switches failing?
>>>> 
>>>> 
>>>> 
>>>> Not sure exactly when Bosch started sealing the TPS, but it seems it was
>>>> after the last 928 left the factory. Presumably they started sealing the
>>>> part due to feedback about earlier ones failing. These newer TPS also have
>>>> the internal connections crimped as well as soldered, because the failure
>>>> mode was often due to the internal solder joints cracking and becoming
>>>> intermittent.
>>>> 
>>>> Best regards, 
>>>> 
>>>> Jonathan
>>>> 
>>>> 
>>>> 928 GT 1991 Amethyst Metallic
>>>> 
>>