Hi everyone
Was wondering if any one has tried one of these circuit testers
as some of you know I got a no communication with engine control module/ car won't start j gate locked in park steering column lock will not disengage
so far engine compartment relay #4 throttle body has power at pins 1&3
No power at ecm connector plug pin 134 or fuse 18
when jump pins 1 & 5 have power to fuse 18 pin 134
and can hear throttle body make a noise
So thought I'd try a different approach and then checked pin 2 relay #4 ground/signal using mitimeter managed to trace relay #4 pins 2& 5 to the 42 way connector plug as they should so know they good
next
Engine compartment relay #5 engine management system
Did the some checks power at pins at 1 & 3
once again using mitimeter i tested pin 5 which i found went to 42 way connector plug
But when I went to test pin 2 ground/signal I can not find where that wire gos
I have tried to find a wiring diagram regarding the 42 way connector plug but had no luck so far

So was wondering if anyone on here has tried one of these short circuit/open circuit tester,s
Thanking you
Darrol

 

Darrol,

Sorry, no experience with that tester.

Would like to help chase down this problem, but am having trouble keeping the details straight with so many open threads on the same general subject. Even the simple stuff, such as what year is the problem car? I tried digging through several threads but no joy.

In the kindest, gentlest manner of suggestion, you'd be a LOT more likely to get this resolved if you could stick to one thread so we can help. I've lost track of how many threads are open.

Which wiring diagram are you using for these relay sockets? If you've got a mystery wire that should have a ground, have you considered temporarily adding one and see if that helps? Might be a lot easier than digging under the dash or wherever a possible wiring fault may be.

 

Hi Karl
thanks for reply
sorry for the novel

Ok back to being
2003 str
First problem was driving along would get park brake fault
So took vehicle to auto Electrician to get it fixed
They installed replacement park-brake module
There Apprentice noticed when scanning car they had no communication with engine control module but car ran fine
The apprentice then tried to reconfigure ecm then car would not start nor get j gate out of park
but when I scanned car the only module with no communication was the ecm

I then sent ecm away to be looked at and was told there was no sign of damage but could have a faulty processor

I purchased a replacement ecm all numbers Identical
Had that cloned
Still no start but now when I scan car I have abs not configured
No communication with climate control
No communication with radio
No communication with park brake module
No communication steering column lock can not unlock steering wheel
Pats code started which was 15 key not recognized
I managed to get that sorted out

Next started testing fuses/relays
Purchased 10 new relays from sng Barratt uk
Bench tasted all fuses using 12 volt power supply and a small 12 volt motor to see if fuses had any power drop all tested fine

Then tested all fuse boxes and noticed only fuse that had no power was fuse 18 throttle motor
so started looking at relay pins and ground
Then tried to work out what relay was for ecm
So started looking at power and ground at ecm connector plug the correct pins had power and ground Except pin 134 which goes to fuse 18

So jumped relay pins 1 & 5 got power to fuse 18 and ecm connector plug pin 134
Then started testing wiring for Continuity so disconnected the 42 way connector plug
Tested relay #4 pins 5 & 2 is ground had continuity at 42 way connector plug for both pins so wiring good
the other day I decided to test engine compartment relay #5 engine management system
Tested pins 1 & 3 12.8 volt
so decided to test pins 5 & 2 relay #5
Pin 5 had Continuity between pin 5 and 42 way connector plug
Pin 2 ground had no Continuity at 42 way connector plug
so now trying to figure out where that wire goes
Since relay pin 5 went through to 42 way connector
I began to wonder if pin 2 did the same
Since relay #4 did
so that why I thought circuit tester might work as you connect to pin you want to test and trace wire by tone
Ignition switch is brand new as well
I also decided to jump relay 20 starter motor and it cranked over
Hope this clears some questions up

Thanking you
Darrol

 

I, too, was wondering lately, which model it was...

> They installed replacement park-brake module
I either missed that or forgot that.
They might have used a wrong module, or a module, which was way more defective than your old one.
Did they give you the old module? Have you ever tried to put the old one back in?

No, I do not know that tester, but any multimeter in continuity-testing-mode will do that...

 

Hi Peter
Yes I thought I would give the circuit tester a go got nothing to lose

I was ment to be back in the UK now
But managed to swap with one of the other engineers who had never been out of new Zealand so him and his wife are staying at or place in uk for the next 4 months
while I say in nz
Just a bit worried about them using our jaguar,s
over there
As here he has a Hybrid Toyota Prius
so I think the two 5.0 supercharged jags might be a bit of fun to get used to

I will let you know what thes tester,s are like very cheap
Around $20 Australian dollars

 

I have and use the General Tech. FF300. It's now been replaced by the FF3310.





Along with this tool I use and recommend getting a Power Probe too. They come in different versions but this tool can supply a ground or 12 VDC as needed to the circuit. Plus has very long leads so you can go from bumper to bumper on the car.
.
.
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The EMS control relay (R5) is turned on or off by a switched ground from the PCM. If the PCM is still not powering up properly (root cause still unknown), R5 will stay in the relaxed position. Similar to that other fuse you were chasing, this is a symptom of an inoperative PCM, not the root cause.

2003 wiring diagrams here:

JagRepair.com - Jaguar Repair Information Resource


Scroll down to figure 01.7. Relay R5 is shown near the upper left corner. Note Diode #4 in the circuit between R5 socket #2 and connector PI41 (42-way connector). If you saw no continuity between those two points, switch your meter leads and try again. Most likely you will now see a fraction of an ohm (normal) through the diode.

 

Hi Karl thanks
After checking wiring harness for ecm again which seems fine with only pin 134 and fuse 18 not receiveing power
I now going to start looking at the general body control module as from what I have read that can cause no communication issues with the ecm
finally managed to get steering column lock to unlock so made a little progress
cheers
Darrol