Hello everyone.

I am facing problems (C1255 EBTCM internal malfunction) in my ABS module and decided to take it apart. I disassembled the EBCM from the BPMV, and dissoldered the upper(power board) from the gel-covered board.

I am trying to replace components in the upper board that may be bad (one of the capacitors is cracked and another one looks like suffering from heat damage), but I would like some help with the identification of the components if anyone with electronics background is able to.

Board is marked 217C174 P5 E00383B217C174 P4, and it is for a M type unit (Delco ABS-5/TCS/MSVA2 model 16257049 - without active handling, only traction control).

The components I was able to partially identify are:

2 relays (Bosch 0332019152), available ebay and other places
a power transistor - M 0035 745 - ** specs? - (CR2)
1 big/blue electrolytic capacitor (nichicon 820uF 25V ) (C4)
2 big/red varistor 1687 9748 - **specs? - manufacturer Harris (currently Littelfuse) - - 16mm disk - voltage suppression purpose (RV1 and RV2)
2 black diodes 40xx 3507xx - **specs? (CR4, CR3)
1 big/gray diode xx 7K C - **specs? (CR1) .

small yellow axial ceramic capacitors:

FC2 9744 - K5R 104K (0,1uF) (C1, C3, C5, C6, )
TV5 9746 - K5R 102K (0.001 uF) (C2, C9, C10, C11)


if anyone has corrections or better indications for the above numbers (especially those with - **specs?) it would be great as the numbers above do not identify the components and therefore we cannot find to buy.

Thank you.



big eletrolitic capacior 820uF 25V

K5R 102K

(2x) 1687 9748 / FC2 9744 / (2x) K5R 104K / TV5 9746 /

Cracked capacitor


TV5 9746

K5R 104K

FC2 9744

 

The red things are probably PTC thermistors which are there to limit the current.

 

Thanks for the indication. I found out that the "H" symbol is in fact the american manufacturer Harris. Harris sold its voltage suppression division in early 2000s to Littelfuse. I think this is a MOV - metal oxide varistor (i.e. a component similar to a zener diode, but with infinite resistance until breakout voltage is exceeded, in which case it will become a wire (very low resistance), dumping the peak/transient noise and voltage to ground and protecting the system upstream). I tried to contact Littelfuse for the specs, but so far I got no answer. I imagine they will say this is proprietary information of GM. Normally the test to determine the breakout voltage is a destructive test so I don't intend on putting this to the test...

 

Call Marc at Vettenuts and ask him if he has ANY damaged early C5 EBTCM that he can sell for parts. Cant hurt!! Might get LUCKY for cheep.

Bill

 

If you look into this tread you will see that Cadillac Seville and Eldorado seems to have to the same top board as 97-00 Corvette .
Probably cheaper to get a used Cadillac ebctm then a used Corvette ebtcm unit


https://www.corvetteforum.com/forums...tc-1243-a.html