History of Bosch CDI ... toubleshooting info, parts list changes, and schematics ...

[oldewurtel]

Dear all,

I´am new in this board and therefore I want to give a short introduction of myself:
My name is Kassen Oldewurtel and I live in the southern part of Germany (in the near of Stuttgart, as you know from BOSCH, PORSCHE and of course Daimler now w/o Chrysler).
I own a ´87 3.2 l 911 convertible and a car for "normal use" (1.9 l Audi A4 Avant TDI)

As I do all maintance on my cars by myself, I was asked to repair a CDI Box BOSCH "0 227 200 001" from a collegue of mine.
Due to a wrong cabling the SCR was gone "into the semiconductor heaven".
The original equipped type (AEG T6N500COB) is obsolete and not longer available.

What is the suggested substitution with identical (or better ) electronic and mechanical (M6 stud) figures??

I took the TIC126N (appr. $2.00 each) in combination with a selfmade (turned and milled) adaptor.
But this is a rather complex solution (pls see picture)

Regards
Kassen

[HKZ Bob]

Hello Kassel

do you like to use OEM design or the T-220?

Use a 2N6509 as a T220 replacement

Bob

[oldewurtel]

Hello HKZ Bob,

thanks for the reply,

I would like the OEM Design with the M6 stud.

Do you know a supplier or distributor for this part?

Regards Kassen

[HKZ Bob]

Go to http://www.rsonline.de

Look for Thyristor 25RIA120M.

Order no. 395-2869

Regards Bob

[ischmitz]

Kassen, that is a funny and ingenious design. But why bother to get an M6 style device in the first place. You could simply mount the TO220 housed device instead. Finding a TO220AB housed device with isolated mounting fin make it even easier.

Bob's suggestion is a part readily available in the U.S. but the TIC126 series seems equally suited. I can seem to find it from the U.S. suppliers but I remember that the TIC series is used in Europe quite often. TIC106 was what was used in old equipment for light controllers. The TIC126 seems to have all required ratings to surpass the original AEG device.

As an interesting side note the TIC126 is listed on Conrad's website as an International Rectifier part. However, I don't think IR makes it.

Does your box work after you put the TIC126 in?

Cheers,
Ingo

[ischmitz]

Originally Posted by HKZ Bob

Go to http://www.rsonline.de

Look for Thyristor 25RIA120M.

Order no. 395-2869

Regards Bob

won't work - ask me how I know......

[oldewurtel]

Hi Ingo,

I tested the device on my workbench w/o ignition coil (it´s still in the car and therefore 35 km away....).
I used a resistor (180 ohms) instead and looked at the output with a DSO.
The box sounds terrible, but I think that´s normal .

I was completely suprised to find the Test Manual and a (selfmade) circuit diagram in this board. I am able to see the red illuminated "BOSCH" sign in Stuttgart/Schwieberdingen from my kitchen window, where this box was developed, but no chance to get any information about this old stuff .

The final test (in the car) is next week and I`am looking forward to this test (with TIC116 or TIC126). The TIC126 will arrive tomorrow.

Greets Kassen

[Early_S_Man]

Greetings, Kassen, from Texas!

Bosch test documents specifically say not to use a resistive load on the CDI unit ... only a proper coil!

[jmchrist]

Sorry for this late answer.
I have used a 2N692 as a replacement (with the correct TO-48 case).
I did it only once without problem even though this model is not specified for Toff.
The 2N692A is specified with a Toff of 15 µs, if you can find it.
Hope this help.

[chb]

hi at all!!

I am new here and I hope you can help me

the big condensator 1 227 330 003 is shorted, does someone know what new element I could build in in stead of this?

bosch says me that they don´t have it anymore.

thank you very much!

regards

chris

[Joe Bob]

Lot of those parts are NLA, try contacting Loren or Ingo. Early S Man passed away a few years back.

[RWebb]

It's good to see that Warren lives on in these forums.

Maybe someone who knows his family would like to contact and tell them as a sort of honor.

[jmchrist]

the big condensator may easily be replaced with a metalized polypropylene condensator of the MKP family.
A MKP condensator of 1.5 µF 630 V is the correct value to choose and can be obtained from any electronic parts retailer.

[wwest]

condensator...what is hell is that...?

[jmchrist]

"capacitor" is better, sorry.

[dicklague]

Big round things inside the CD box. Quite available from electronics parts suppliers, you march the voltage and capacitance rating.

All the parts inside the box are available......not from Bosch, but out there in the electronics market.

[chb]

thank you very much for the info!

I will try to get it in a electronic shop!

thanks!

regards

chb