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Re: Dead MX-3

Posted: June 28th, 2004, 1:44 am
by Gro Harlem
Damn you know your electronics.

There aren't any parts places that carry remanufactured parts? Thats what we have in the states. Just go to the parts place, get a remanufactured distributor and you also get a lifetime warranty. I've already used that warranty TWICE since i've bought my disty back in october.

I'm on my 4th right now...what a peice of crap!!


I tried to rig a GM HEI ignitor module to bypass our existing module but it didn't work. Some guys on Probetalk did this mod with success, but I must have screwed up the wiring. I'll try later on in the summer whne I get time to mess with my 3.

Re: Dead MX-3

Posted: June 28th, 2004, 3:12 am
by IanL
Originally posted by Mariusz:
The only pin to which transistor is connected (3 Pin connector) is B, on the 6 pin connector E , F
So the wiring of the transistor is (6 Pin) F to Base , (3Pin) B to Collector, (6 Pin) E to Emitter? It is very important because i will try to switch only the transistor.
Correct for the Base and the Emitter. Not quite correct for the Collector. Collector is wired to 3-pin A directly, and to 3-pin B through a resistor in the module (don't know the value). A goes to the Diagnosis Connector, and B to the Tachometer.

I hope it works, just replacing the transistor, but your Primary Winding is 1163 times the maximum permitted resistance, so I fear it will not, because the Primary current will be too small, and Vce will be too low. :(

WARNING: 3pin connector is wired differently in later cars - see post above in this thread.

<small>[ June 28, 2004, 02:23 AM: Message edited by: IanL ]</small>

Re: Dead MX-3

Posted: June 28th, 2004, 4:25 am
by mmx01
I have such 3 pin connector.

:) .


The parameters of the transistor which i want to use:
http://katalog.elektroda.net/dwpl.php?file=data/BU/BU931.pdf -> Download

<small>[ June 28, 2004, 04:16 AM: Message edited by: Mariusz ]</small>

Re: Dead MX-3

Posted: June 28th, 2004, 5:51 am
by IanL
According to the Mazda manuals, the early distributors were wired with the collector to A(3pin), and through a resistor to B(3pin), the base to F(6pin) and the emitter to E(6pin). C(3pin) is for the IG supply to the Primary.

The later distributors have the collector to B(3pin) and through the resistor to C(3pin), the base to F(6pin) and the emitter to E(6pin). A(3pin) is for the IG supply to the Primary.

If your distributor looks like the photograph, it may be that you have the later type, and your Primary is between A(3pin) and B(3pin).

Your English is better than my Polish :) so I will try to explain again. You have measured 1kOhm between A and B. This measurement is supposed to be (for the later type distributor), 0.49 to 0.73 Ohm (WITHOUT THE k). So your Primary winding is more than one thousand times the resistance it is allowed to be. It is unlikely that it will ever work. You need a new coil, and you can only get that by getting another distributor.

Re: Dead MX-3

Posted: June 28th, 2004, 6:22 am
by mmx01
OK, one more thing, which of these pins on the picture is A ? first on the left ? B is known :) and the C is near the coil tower ?.

If I switched the C and A during measures values are like these:

A-C 1kOhm
A-B 1Ohm
B-C 1kOhm
C-HT unknown, I don't have coil with me in the work :)

the primary is A-B secondary C-HT no it's clear.

Re: Dead MX-3

Posted: June 28th, 2004, 9:25 am
by IanL
Originally posted by Mariusz:
OK, one more thing, which of these pins on the picture is A ? first on the left ? B is known :) and the C is near the coil tower ?.

If I switched the C and A during measures values are like these:

A-C 1kOhm
A-B 1Ohm
B-C 1kOhm
C-HT unknown, I don't have coil with me in the work :)

the primary is A-B secondary C-HT no it's clear.
Yes, that's right, A is near the 6pin, C is near the coil tower. A-B 1 Ohm is a bit high, but depends how sensitive your measurement was. A-C and B-C is the resistor in series with the tachometer. A-HT and C-HT will measure nearly the same, because the resistance of the Primary is so low it does not show, and the series resistor is only 1 kOhm.

So if you did switch A and C, it looks like your coil could be OK.

Good luck with the transistor.

Re: Dead MX-3

Posted: June 28th, 2004, 10:58 am
by mmx01
I've took all these parts to the guy who has equipment to diagnose it. The coil is OK, also the ignitor is OK, also the hall sensors are OK, so the distributor is OK. This is a good and bad news, i don't spent a lot of money for distributor but I must find a reason of a spark lack. The spark from my coil in the lab was 10cm high.

Re: Dead MX-3

Posted: June 28th, 2004, 11:01 am
by mmx01
I've took all these parts to the guy who has equipment to diagnose it. The coil is OK, also the ignitor is OK, also the hall sensors are OK, so the distributor is OK. This is a good and bad news, i don't spent a lot of money for distributor but I must find a reason of a spark lack. The spark from my coil in the lab was 10cm high.

Could you send me detailed 3pin terminal description from the engine side ? where is ground where is +12V etc. 6 pin connector is easy (1,2 hall sensor 1 - 2,3 hall sensor 2 - 5,6 Emitter,Base NPN)

I must check the harness now for shorts and brakes.

Re: Dead MX-3

Posted: June 28th, 2004, 11:59 am
by IanL
3pin A - +12V from START and RUN positions on ignition switch, fed from Main Fuse 100A. This line appears to have a capacitor built-in to the distributor connected onto it, the other end of which is grounded - check this is not defective!!!

3pin B - igniter collector to data link connector only

3pin C - igniter collector through resistor to tachometer only

6pin A - to Ground on right side of engine (grounds the emitters of the Camshaft position sensor (CPS) NPN amplifiers)

6pin B - +12V from Main Relay in main fuse block, fed from Fuel Injection Fuse 30A, goes to CPSs only

6pin C - collector of No 2 CPS amplifier to 3G on ECU

6pin D - collector of No 1 CPS amplifier to 3E on ECU

6pin E - emitter of igniter NPN to Ground on right side of engine

6pin F - base of igniter NPN to 1G on ECU

I can send you a scan of the distributor internal wiring if you need it - PM me your email address.

<small>[ June 28, 2004, 02:05 PM: Message edited by: IanL ]</small>

Re: Dead MX-3

Posted: June 28th, 2004, 1:54 pm
by mmx01
I've done some tests from the engine side:

6 pin connector: all OK

3 pin:

A, +12 OK
B, if connected to the ECU as red -> break.
C, if connected to the ECU as yellow/blue -> break.

Can someone can confirm where the B and C are going to ECU ?

Re: Dead MX-3

Posted: June 28th, 2004, 2:20 pm
by IanL
Originally posted by Mariusz:
I've done some tests from the engine side:

6 pin connector: all OK

3 pin:

A, +12 OK
B, if connected to the ECU as red -> break.
C, if connected to the ECU as yellow/blue -> break.

Can someone can confirm where the B and C are going to ECU ?
B and C do not go to the ECU, they only go as described in my post above.

Check B and C for a short to ground, as this could lose the igniter output.

Re: Dead MX-3

Posted: June 28th, 2004, 2:39 pm
by mmx01
So the distributor is OK wiring is OK, but there is no spark what the f... is going on ?
How can i diagnose injectors and fuel pump ?

There is no any errors on ECU.

Re: Dead MX-3

Posted: June 28th, 2004, 2:56 pm
by IanL
If you have an oscilloscope, put it onto ECU 3G and 3E in turn, crank the engine and check for a crankshaft position signal. If that's ok, put it on 1G, crank again and check for spark drive signal out of the ECU. If the CPS signal is ok, but the ECU signal is not, it must be the ECU is dead.

Apology - in my previous post I said 2G and 2E - it should be 3G and 3E - I've edited that post.

<small>[ June 28, 2004, 02:07 PM: Message edited by: IanL ]</small>

Re: Dead MX-3

Posted: June 28th, 2004, 3:12 pm
by hgallegos915
Hmm, im suprised that know one has told him that the most possible thing is that his timing belt snapped. Therefore when the starter just spins..its turning just the pistons. If it was the belt..then your valves are bent by now since u started it alot of times. Thats why ecu doesnt register codes. Not familiar with the k8...but im guessing that would be it if it has a timing be;t or chain?

Re: Dead MX-3

Posted: June 28th, 2004, 3:17 pm
by hgallegos915
Oh, my bad..he sais the finger does mopve when starting..then i guess that discards the snapped belt..how about a belt that jumped a thread?