Car stuck in garage - they need some help - Page 4

roverbarmy · 12th February 2015, 07:56

Quote:

Originally Posted by marinabrian

The screenshot shown is that of an NNN500340, the NNN100720 as fitted to early automatic cars is electronically very similar in architecture.

There is only one capacitor fitted to the late ECM, and a blocking oscillator is fitted in place of capacitor two to generate approximately 30v.

The NNN100692 as fitted to the early manual cars, has two identical injector driver circuits, so both capacitors read approximately 80v

The injector solenoids are 12v, and the ECM generates the injector dwell time with pulse width modulation, using the 80v rail chopped rapidly.

There you go, bet you wished you hadn't asked now

Brian

I can only get by when the laughing shaft gets caught on the giggling pin. (Easily resolved by copious amounts of lubrication of the throat sensor via the input nozzle)!

marinabrian · 12th February 2015, 07:57

For the benefit of Graham the OP, sadly the wiring diagrams do not show anything other than the interconnects between the ECM and the throttle demand potentiometer, so back to plan A I'm afraid.

See the attachment for detail of this

Brian

Stickman · 13th February 2015, 05:01

Quote:

Originally Posted by marinabrian

No Chris, what you are seeing is an immediate post start reading with the HRW activated due to low temperature.

Add into the equation I had just programmed the ECM, which involves having the ignition switch in position 2 with the engine not running, so glowplugs and fuel pumps all take their toll on the battery.

The normal readings are circa 14.2v, and my car quickly recovered to this after a couple of minutes.

If a battery has diminished capacity, it will accept a surface charge very quickly, however as the battery is good on my test car, it is slower to react.

Brian

Thanks Brian for the explanation

Regards
Chris

Diamondhead · 24th February 2015, 12:08

Hi All,

Just thought I'd give you all an update.

I now have a working car.

Fitting a new accelerator peddle has got me going. Whether this was the fault all along and not the ECU we will never know. I'm a little annoyed at the garage sourcing a second hand accelerator initially, which looks to have been faulty. If they had gone with new from the start I probably would have saved some money and a lot of time.
However I'm just glad to have the car back and running.

I cannot thank Brian enough for his time and knowledge in helping me sort this. The guy is a hero.

Cheers,

Graham.

Phil-T4 · 24th February 2015, 13:00

See post #2

chipsceola · 24th February 2015, 13:07

Quote:

Originally Posted by Phil-T4

See post #2

And yet another reason to join and support the 'forum'.

Help and advice given here is more than value for money when it comes to identifying and fixing problems - a collective wealth of knowledge you will find nowhere else, priceless, and yet available for such a small subscription as a new user said only a few days ago,

hamster19 · 24th February 2015, 15:27

'Superbrian' strikes again

MangoMan · 24th February 2015, 15:35

Quote:

Originally Posted by Phil-T4

See post #2

Gee, that would have saved nearly a month of phart-aarsing around!

marinabrian · 24th February 2015, 17:54

Quote:

Originally Posted by Phil-T4

See post #2

Exactly, this is what I initially said to Graham when I first spoke to him on the phone

Quote:

Originally Posted by MangoMan

Gee, that would have saved nearly a month of phart-aarsing around!

It certainly would have Bill

Never mind though, Graham's car is up and running now, and hopefully he will be able to enjoy it now

Brian

sjc · 24th February 2015, 21:26

Well guys.
Yet again the knowledge on this forum never ceases to amaze me.

24th February 2015, 12:08	#34
Diamondhead Newbie Rover 75 Classic Join Date: Jul 2011 Location: Nottingham Posts: 12 Thanks: 0 Thanked 0 Times in 0 Posts	Update Hi All, Just thought I'd give you all an update. I now have a working car. Fitting a new accelerator peddle has got me going. Whether this was the fault all along and not the ECU we will never know. I'm a little annoyed at the garage sourcing a second hand accelerator initially, which looks to have been faulty. If they had gone with new from the start I probably would have saved some money and a lot of time. However I'm just glad to have the car back and running. I cannot thank Brian enough for his time and knowledge in helping me sort this. The guy is a hero. Cheers, Graham.

24th February 2015, 21:26	#40
sjc Posted a thing or two MG ZT-T 180 Sports +, 2007 completely restored XJ 4.2 LWB Sovereign,Noble M400,LR Discovery 3 Join Date: Dec 2009 Location: Little Baddow Posts: 1,315 Thanks: 65 Thanked 148 Times in 70 Posts	Well guys. Yet again the knowledge on this forum never ceases to amaze me. __________________ The 75... " It's lovely isn't it ? Makes you wonder why people are obsessed with modern rubbish". Tiff Needell

24th February 2015, 13:00	#35
Phil-T4 I really should get out more....... MG ZT-T, Rover 75 Tourer Join Date: Mar 2011 Location: Olney Posts: 2,969 Thanks: 245 Thanked 1,088 Times in 657 Posts	See post #2

24th February 2015, 15:27	#37
hamster19 Gets stuck in tourer conn CDTI Join Date: Feb 2014 Location: morpeth,northumberland Posts: 834 Thanks: 381 Thanked 112 Times in 105 Posts	'Superbrian' strikes again