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Discussion Starter #1 (Edited)
One of the many cars I'ev mangaed to break this week is Marians Figaro. :tdown: I had to do a brake overhaul followed by fitting new plugs ( started straight away ) and then rotor ,cap and leads at which point it refused to restart. I refitted all the old stuff and it still wouldn't start .

Tried to check for a spark at the king lead from the coil and that was good

I then managed to flatten the battery ,put it on charge and walked away . I thought Camshaft Angle Sensor had failed so wasn't a happy bunny.


With a better attitude today I started again . Used a bulb to check thw switching at the coil and then also checked the injector pulsing with a noid , all good :tup: There's now no spark at al at the kinglead so I've pulled the coil and ignition module to check what's going on. Primary winding resistance is 1.1 and secondary is 9.85 on both terminals


Meanwhile any idea if the 3 prong ignition module can be checked for function ?
 

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If its anything like the one used on the range rover efi lucas hotwire type Kev then Yes and it shows you how within the Haynes manual .................

Do you think i can find mine to scan for ya i think i must of let it go with the injection stuff i sold :sniff:

There is another way about checking to see if it works ........................... Lick your finger and insert youll soon find out if it works mate :pmsl:
 

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Discussion Starter #3
Thanks for the helpful advice Vince ...NOT :incheek:

I've just cleaned up the earth terminal that bolts to the coil ( insulated by rubber washers from the coil mounting bracket ) and put it all back together ,still no spark.

Then I've run a check on that terminal with a multi meter and ,with the igntion turned on, I get a reading of 3.6 volts between that earth terminal and the earth battery post ? Is that correct ?

If I discnnect the 2 pin switching plug to the coil that reading goes .
Surely that means one of the coil windings is 'leaking to earth?

It's not a standard cylinder type coil ,more the style that you find on some Fiats with an open winding on show.

In fact it's exactly like this one:incheek:

http://cgi.ebay.co.uk/Nissan-Figaro...arts_Vehicles_CarParts_SM?hash=item1e5b456a70
 

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Discussion Starter #5
Cheers Vince . I've been a member on there since we got the car but didn't find that thread while searching :tdown: After a read he had a spark but ours is awol hence believing it's an ignition module or coil issue ,neither of which is cheap hence I want to get the right one first time round.

The guys on the Micra March forum have been helping as well as they use the same engine only with a supercharger as well as the turbo :shock:
 

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Kev looking at the pic of the coil it looks like the ignition amplifier is attached to it, these are common to fail, or as you say crank sensor if fitted, you should be able to get details to check the values from workshop manual or nip to your local garage and ask to look on autodata for info.
 

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Discussion Starter #7
Workshop manual ? It's in Japanese ! As an import there is very little info about and I seem to be asking questions that most involved with servicing haven't encountered.
I've replaced the ignition module and still no joy. I'm pretty sure the HT readings are too low so I'm going to recheck the Camshaft angle switching tomorrow and then pull the coil and test off the car to see if I can make it spark .
Code reader comes back as 'No faut Found' .
 

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My name is Martin
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Nissans huh :slap:

That bit on the side of the coil is called the power transistor. It amplifies the signal from the ECU.

You should have 3 terminals on this. An earth, a feed from the ecu, and a connection to the coil earth. I'm sure the coil gets its power via an ignition relay so should see full voltage. The ECU will send a signal to the transistor 'base' terminal. This in turn activates the transistor and so it closes the circuit between the coil earth to the transistor earth (acts as the contact breaker in effect)

The ECU is designed so it doesnt have to collapse the whole of the primary field. Thats a fair old load, so by getting the transistor to do it makes the ECU's job lighter.

In terms of testing, search out how to check the continuity of a transistor. It's simple, but you're checking for directional continuity, so you may need a diode to help identify this.

Doh. After typing this I just noticed you've changed the ignition module, so it might be un-needed info above. if you still want to check the continuity of the transistor let me know.

I would check the ignition module is nicely earthed and that the ecu signal is reaching the transistor. Also check continuity between the transistor and coil earth and the coil voltage.

You may want to do this whilst the engine is stationery and cranking. If you have a spare CAS (crank angle sensor) you can spin this and it fools the ecu in to thinkin the engine is spinning, so it makes it easier to monitor the injectors and coil without unnecessarily cranking the engine.

One final note, I think Nissan uses a blue wire from the coil earth to the tacho. If this has messed up and continously earthing out the coil it wont start, so check that too.

Good luck. I bet whatever it is, it's a very simple fault. Once you find the bastard thing of course :sniper:
 

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Discussion Starter #9 (Edited)
Thanks , some interesting info and I've a better understanding of what wires goes where , I'll run it through this morning.

Apparently you check the module by testing directional flow on the 2 and 3 terminals , should only flow one way.

I was thinking about testing the coil off the car to get a spark but the isolated body was confusing me .
 

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Discussion Starter #10 (Edited)
Do you by any chance know what the secondary winding resistance should be on that style of coil , I'm getting 9.85 ?
 

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My name is Martin
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I'd have to dig out a Nissan service manual to find out for you
 

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Discussion Starter #12 (Edited)
I've just done 1.5 hours ,backs killing me and my brain REALLY hurts. I'm getting old and looks like it's stopped figuring out what the hell is going on :shake::tdown:

I'm definitely getting switched ECU signal (red/white wire ) but it's switching at the coil AND ignition module ( or appears to be ).

Ignition module has :-

red/white =

brown = main earth (?)

white /black=


Coil has :-

red /white =

white/black =

seperate earth lead ( which is testing up as constant negative, no switching )



The tach needle ISN'T twitching when cranking.

EDIT : I've just switched my multimeter to diode ( never tried this before ) to test the Ignition module . I'm getting readings both ways on old AND new module , is that correct ? Surely I haven't got a knackered NEW unit as well?

Plus, as the ignition module has a steel back that bolts to the coil mounting bracket I'm assuming that is the way the central brown terminal get's its earth ? If so shouldn't I get a continuity reading between that central brown terminal and the outer steel casing ?
 

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My name is Martin
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You mentioned you had some wiring diagram in japanesey, I can't read it but are you able to scan and pop it up on here?
 

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My name is Martin
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Don't do that then. Does the Micra club have one available for download from the net?

Do you know where the ECU is. Can you see if the coil gets power with this removed?
 

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Discussion Starter #16
Actually, I've just remembered I bougta Micra manual in the vain hope it showed something useful , I'll check it out.

I'm presumoing the switching earth terminal on the coil connects ( via the loom) to the ign module and then the central brown must earth out elsewhere on the body , I'm confused ?:mooooh::wacky:

The coil is off atathe mo, going to try to rig it up and see if I can get it to spark to rule it out.
 

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Discussion Starter #17 (Edited)
I've picked out the coil wiring from the Micra manual . Some of the colours are different to mine but I 'think' it's the same otherwise . I'm just not seeing the crcuit or flow in my minds eye . I'll make the excuse that the pain killers are fogging my mind .:tdown:

Which terminals do I need to connect what to test the HT output via a spark plug.
 

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My name is Martin
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OK, the R (26) wire to the ignition module should be switched on and then off to release the field in the coil. If current is at R, then current should flow from the W/R on the coil through the transistor to earth, energizing the coil. Upon releasing the current in R, the transistor should not allow the coil to earth.
 

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Discussion Starter #19
So R is the switching from ECU and should be worked by the signal given from the CAS? Should that be positive or negative ,I think the dizzy earth (negative) switches ?
 

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Where traditionally you'd expect it to be a negative, I'm sure the feed from the ECU will be positive to activate the transistor (acts as a relay in principal).

The CAS is unlikely to be faulty. If the injectors are clicking then the CAS is fine. It would be great to see a pic of the CAS if you can inc the 4 pin plug. Chances are another nissan one may fit which really helps testing as I explained before it means you dont need to crank the engine and of course it's silent so you can hear the fuel pump prime and the injectors click
 
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