MrSafety
Newbie at Heart
- Joined
- Jun 27, 2010
- TDI
- 2002 Jetta TDI/ALH/01M-'80 240D Mercedes/'81 Rabbit "Caddy"/'99 Lexus ES300
OK, I think I have a real challenge here.
[1] First, we had to go internal on our IP to solve its 3-week NO START problem.
[2] My INDY VW/Audi shop "tweaked" it with the latest ver. of VAG-COM from Ross-Tech.
[3] But the computer keeps throwing off code P1562... about every 2 weeks!
[4] I have completed resistance tests on these pin pairs looking into the IP's 10-conductor harness cable:
.....1-to-2 and found ~6 ohms
.....2-to-3 and found it was open... no continuity!?
.....5-to-6 and found ~1 ohm
My take on the results of my reading above on pins 1, 2, & 3 is that
there is a good chance the wire in the harness from pin #3 might be failing
and loses continuity after the car/engine/IP fully warms up!
.................
I'm pretty good at slicing/dicing and repairing harnesses,
so I'm thinking about the following diagnostic/(possible repair) steps:
(a) cutting off the harness cable about 3 inches from the IP...
leaving enough to splice to later (hopefully),
(b) measuring resistance from that point into the IP to
see IF I get the same readings as above and
.....also before cutting, take readings between pins 4-to-7
( these run to my new FTS on my last IP internal inspection )
.....to compare after cutting the harness cable.
My logic in this is that IF these conductors appear good from this point looking into the IP,
then I will conduct similar (but individually end-to-end) continuity tests on each of the 7 conductors
that run into the IP's QA/FTS/Modulating Piston Displacement Sensor (MPDS) in this bundle
harness from the cut back to the pins in the connector...
and in doing this I will test each wire individually and
bend/flex the short cable to see if continuity is restored and/or broken!?
..............
IF I do find a broken/unreliable wire pin #3 and/or other conductors,
then I will make a reliable repair of the existing harness bundle or rebuild a
new harness to and spliced into the 10-conductor in-line connector!
Q1 - Can anyone follow my too lengthy a discussion which helps me to test the logic of such diagnostics?
Q2 - Does anyone have suggestions for other checks/tests that I should try first.
...............
Yes, since I have been into the IP twice before I'm even thinking I might open up the top of the IP and
see IF I can conduct resistance readings for each of these same 7 conductors from the QA/FTS/MPDS
circuit board assembly back out to the pins in the 10-conductor connector!
This would also let me check again for wear metal filings that stick to the magnet on the bottom of the QA assembly!
Your thoughts/suggestions PLEASE,
P.S. - See page No. 66/4 of the Wire Diagrams.
I have a PDF of this wiring IF you want me to send or try to POST it here on the FORUM!
Sam Ross
[1] First, we had to go internal on our IP to solve its 3-week NO START problem.
[2] My INDY VW/Audi shop "tweaked" it with the latest ver. of VAG-COM from Ross-Tech.
[3] But the computer keeps throwing off code P1562... about every 2 weeks!
[4] I have completed resistance tests on these pin pairs looking into the IP's 10-conductor harness cable:
.....1-to-2 and found ~6 ohms
.....2-to-3 and found it was open... no continuity!?
.....5-to-6 and found ~1 ohm
My take on the results of my reading above on pins 1, 2, & 3 is that
there is a good chance the wire in the harness from pin #3 might be failing
and loses continuity after the car/engine/IP fully warms up!
.................
I'm pretty good at slicing/dicing and repairing harnesses,
so I'm thinking about the following diagnostic/(possible repair) steps:
(a) cutting off the harness cable about 3 inches from the IP...
leaving enough to splice to later (hopefully),
(b) measuring resistance from that point into the IP to
see IF I get the same readings as above and
.....also before cutting, take readings between pins 4-to-7
( these run to my new FTS on my last IP internal inspection )
.....to compare after cutting the harness cable.
My logic in this is that IF these conductors appear good from this point looking into the IP,
then I will conduct similar (but individually end-to-end) continuity tests on each of the 7 conductors
that run into the IP's QA/FTS/Modulating Piston Displacement Sensor (MPDS) in this bundle
harness from the cut back to the pins in the connector...
and in doing this I will test each wire individually and
bend/flex the short cable to see if continuity is restored and/or broken!?
..............
IF I do find a broken/unreliable wire pin #3 and/or other conductors,
then I will make a reliable repair of the existing harness bundle or rebuild a
new harness to and spliced into the 10-conductor in-line connector!
Q1 - Can anyone follow my too lengthy a discussion which helps me to test the logic of such diagnostics?
Q2 - Does anyone have suggestions for other checks/tests that I should try first.
...............
Yes, since I have been into the IP twice before I'm even thinking I might open up the top of the IP and
see IF I can conduct resistance readings for each of these same 7 conductors from the QA/FTS/MPDS
circuit board assembly back out to the pins in the 10-conductor connector!
This would also let me check again for wear metal filings that stick to the magnet on the bottom of the QA assembly!
Your thoughts/suggestions PLEASE,
P.S. - See page No. 66/4 of the Wire Diagrams.
I have a PDF of this wiring IF you want me to send or try to POST it here on the FORUM!
Sam Ross