60 replies to this topic

[Johnboyhgt]

If your really struggling Chris and myself could double up on this, car would need to come to yorkshire though.

 

Just an option.

[Exmantaa]

Battery = 12.4v - Yep

big X1 plug = 12.4v (goes to starter relay and feed of the K18 relay) - yep


X2 pin 5 (green) measured only 9v (comes from fusebox 7) Ecu shows this 9volt in the logs. Drops to 7volt on starting... - yep

 

Check voltages on the fuse box in the front (Both sides of each fuse! After you confirmed the direct battery voltage):

Fuse #2,5,6,7,20 & 22 all switched on by Ignition key.

Fuse #8,9,10,11,12,13,14,15 allways on.

X2 pin 1 unknown; should be 12.4v when K18 is activated. (ground pin X2-12; green/pink wire) - I'll go out check this today


X3 pin 13 unknown (should be always >12v from fusebox 8. Ecu back-up feed) - I'll go out check this today

[Rosssco]

Checked again:

 

 

Battery = 12.4v - Same

 

big X1 plug = 12.4v (goes to starter relay and feed of the K18 relay) - Same

 

X2 pin 5 (green) measured only 9v (comes from fusebox 7) Ecu shows this 9volt in the logs. Drops to 7volt on starting... Checked today with engine cold - 12.0v

 

X2 pin 1 unknown; should be 12.4v when K18 is activated. (ground pin X2-12; green/pink wire) - Can't seem to get any reading on this, ignition on or off..

 

X3 pin 13 unknown (should be always >12v from fusebox 8. Ecu back-up feed) - Can't seem to get any reading on this, ignition on or off..

 

Fuse 7 - varies between 11.8v and 12.2v

 

[Exmantaa]

 
 
Battery = 12.4v - Same
 
big X1 plug = 12.4v (goes to starter relay and feed of the K18 relay) - Same
 
X2 pin 5 (green) measured only 9v (comes from fusebox 7) Ecu shows this 9volt in the logs. Drops to 7volt on starting... Checked today with engine cold - 12.0v  Bit low. should be same as battery voltage  with no load on it, but fuse #7 also measures weird
 
X2 pin 1 unknown; should be 12.4v when K18 is activated. (ground pin X2-12; green/pink wire) - Can't seem to get any reading on this, ignition on or off..

(Ignition on does not matter for this test. Measure voltages on disconnected X connectors; Car side.)
Measure on X2 pin 1; should be 0 volt
connect X2 pin12 green/pink wire to a ground => Switches the K18 relay. You should hear it clicking.
Measure on X2 pin 1; should be same as battery voltage.
 
X3 pin 13 unknown (should be always >12v from fusebox 8. Ecu back-up feed) - Can't seem to get any reading on this, ignition on or off..
 
Fuse 7 - varies between 11.8v and 12.2v => should be a very steady battery voltage! What does the voltage do with f.i the lights on?

What measures fuse #8? (always on power)

[Rosssco]

I measured the voltages at the following fuse locations (with both ign on and off for both):

 

2 - 10.7v

5 - 0v

6 - 11.84v

7 - 12.06v

20 - not used

22 - 0v

 

8 - 12.34v

9 - 0v

10 - 0v

11 - 0v

12 - 11.9v

13 - not used

14 - 0v

15 - creep slowly from 3v to settle at 9.3v

[vocky]

X2 pin 1 unknown; should be 12.4v when K18 is activated. (ground pin X2-12; green/pink wire) - Can't seem to get any reading on this, ignition on or off..

 

correct - it should have 12v when relay K18 is active or when X2-12 is grounded, the K18 supply power is also a permanent 12v which comes from the big fuse FL4 under the windscreen
 

 

X3 pin 13 unknown (should be always >12v from fusebox 8. Ecu back-up feed) - Can't seem to get any reading on this, ignition on or off..

 

 

correct - it should have a permanent 12v from fuse 8

[vocky]

I measured the voltages at the following fuse locations (with both ign on and off for both):

 

2 - 10.7v

5 - 0v

6 - 11.84v

7 - 12.06v

20 - not used

22 - 0v

 

8 - 12.34v

9 - 0v

10 - 0v

11 - 0v

12 - 11.9v

13 - not used

14 - 0v

15 - creep slowly from 3v to settle at 9.3v

 

they should all be around 12v, give or take 0.5v. Certainly not - 10.7v / 3v / 9.3v

 

Fuse 5 and Fuse 22 are ignition switched 12v

 

Fuses 9,10,11,14 should all be a permanent 12v

[vocky]

I suspect you have some wiring corrosion around the front fuse box

[Rosssco]

I suspect you have some wiring corrosion around the front fuse box

 

Doesn't sound good tbh does it 

 

Thing is, car will start 'normally' if left for a while. Only repeated starts fail..

[vocky]

two options;

 

1 - bodge it and wait for it to return

 

2 - replace the loom and stop worrying about it

[Sutol]

Back on Track use a brilliant auto electrician, Toby

He's not the fella they use now, sadly.

[Exmantaa]

 

2 - 10.7v

5 - 0v      => reverse & stop lights not working?

6 - 11.84v

7 - 12.06v

20 - not used

22 - 0v  => ABS...

 

 

 

8 - 12.34v

9 - 0v    => Hazard Warning lights not working?

10 - 0v  => Horn not working?

11 - 0v  => interior light + alarm system not working?

12 - 11.9v  => cooling fan turning slow?

13 - not used

19

 

14 - 0v   => front lights not working??

15 - creep slowly from 3v to settle at 9.3v  => Radio  Weird behavior...

 

Some real dodgy wiring there up front and probably a lot worse when you try to pull some Amps through it...

[Rosssco]

Yeah, who knows! I'm gonna buy the complete loom anyway to fit, although I'll try inspect the front wiring again.

 

At least then I can say I've effectively replaced every major electrical component on the car:

• Alternator
• Starter
• Coil pack
• Injectors
• Throttle body
• ECU
• Crank sensor
• T-Map sensor
• Brown and Grey relays 
• Relay holders
• Engine loom
• Battery
• Earth cables
• Battery Live terminal
• Heater unit (discovered a leak)

 

Edited by Rosssco, 17 September 2019 - 10:21 AM.

[smiley]

wow, that Is one fecking expensive starting problem

[Rosssco]

wow, that Is one fecking expensive starting problem

 

Yep. I'm up to about £850 on parts alone, and coming up for a year out of action, and its still fooked! Plus the body is even tattier because its just been sitting, discs rusted up etc.

 

Never had a car quite this unreliable, but that's part of the joy, right?

[R30SS]

Hi mate. I use Automek in East Kilbride - worth adding to the list. 

 

Their main man Andrew had a racing Elise and has done plenty K series swaps, as well as maintaining a number of customer VX's so he knows every nut and bolt on these. Give him a bell

[Rosssco]

Cheers Ross. I forgot about Automek and that they had Elise / VX knowledge..

 

The car might end up going down the road for some bodywork too, so Automek could be a good shout if it comes to it. 

[Matthew Bentley Racing Ltd]

We are happy to try and help, not sure how far you are from us

 

MBR

[Ivor]

When if does start does it run ok without issue until you turn it off?

[Rosssco]

When if does start does it run ok without issue until you turn it off?

 

Yeah, it seems to run ok initially, but after two or three starts it just goes down hill till it won't even turn over.