Bad ECU 1.6 8v 1990.

[fixkick]

its not a bad DLC ground pin because both the fuse box and DTC 4 pin plug , would not both fail.

[Lynyrd]

[Lynyrd]

The orange cap 10V 47uF is original cap

[Lynyrd]

I cleaned the traces of acid capasitor c4

[Lynyrd]

Is what i can mount this calculator

Original is

33920-60a70
E2T40671
9316B

http://www.noelshack.com/2016-47-1479727...to-013.jpg


this is


33920-60a70
E2T40671
0Z06G

[fixkick]

wow nice photos, THANKS.
that 10v cap is in other circuit,
its ok.
all looks ok.

if the ecu can not flash codes,
and the lamp is ok (non usa) and you lamp tested good.
it can only be these things
bad ecu,
bad DLC wiring.


only 2,
i can take that ecu and bench it
add 12v
add ground
add just 1 lamp to cell pin
then ground the diag pin on ecu and it will flash a huge list of errors, for all those sensors not connected now.


see this
I can do that with only 3 wires hooked up, Power and ground, CEL , then ground DIAG pin.
4 wires counting diag, in hand.

see?
all 60a and 56b and 70B ecu do that, all 89. to 95 here. in usa.

those cap are all the good brands,, not flaky, Rubicons.. I bet all caps there are good. if not put in backwards.

all the electrolytic, caps, are polarized, did you change some?
same with tantalum caps (gum drop look-a-likes)

why is that Hitachi black cap sitting on long legs. someone mess with that, is it backwards too? the PCB silk screen(paint) is clearly marked + (plus)
the caps are usually marked MINUS.
so never put minus to plus or the cap shorts.

[fixkick]

i See damage there.
on the last photo.
is see clear evidence, of damage, and attempted repairs. near R102. (my guess, is this damage was from hot wiring sensors on car, by wild men,(common)
then blew up those parts there, and then attempted repairs, and was not effective or only partially, gaining only backup mode. only.... (my best guess not in MY HANDS)
is that B15 pin damage B is green in this car. (b17,b16,b15 ( B17 is behind B1) if yes, someone blew up the ISC driver, line)
B1 and B7 is 12vdc power.
B2 /B3 is ground. (for power)

I think this ecu is bad.
a bench test is easy if done with care , power and ground and a less that 0.100amp 14v lamp , on CEL. spec for lamp is 0.050amps 50 mA, due to transistor cant do more . than that.
the dash lamp cel lamp, is the lowest ampere lamp in car, not by accident.

if it (CEL) dont flash on demand, it is a bad ecu. 89-95 usa and many more years, in ROTW (rest of the world) on all cars until, around EUROPE EOBD kicked in, (simular to usa OBD2)
some cars sold by suzuki run this old stuff OBD1 (suz) until 2004.
its cheap and keeps car costs lower..

[fixkick]

to test and ecu,
we bench it
look for damage
look for acid(boric) leaks. on caps
look for hacking or poorly done repair, (like yours has)
look for caps inserted backwards, (more hacks)
power it up, see CEL glow.
then see 5v on the 5v pin, if not the ecu is toasted.
then we ground diag, if it dont flash out a stream of many DTC errors. the ECU is toast.
and more lots more tests. (I can do about 1/2) the machine to do them all is $100,000 (i used to program them, in a last life) me retired

[fixkick]

id bet in a shop , we'd get to step 3 and , fail, (toasted is toasted)
i have repaired only bad outputs
and inputs dont fail,they are protected
I have repaired the blown up 5vdc clamp diode that blows the trace off the PCB, if lucking 5vdc returns, on some , the hybrid is blown up and they dont sell any of the expensive parts seen on this PCB.
PCB is the whole main, printed ciricuit board.
those SIP chips are not sold.
the processor is not sold with suzuki code inside (ROM), so it too can not be replaced.

Backup mode kills the CEL dead, (off or stuck on)
if in backup mode that means the main code running, , does tests, and finds the main program can not run. due to some massive, internal main failure
so the activates a BACKUP chip.
the backup is just to move car out of danger, only. say stuck off road or whatever,

personally I never had a old car like this and not have spare ECU
after all they are not getting any more easy to find, and fixing them many times takes 2 or 3 ECU to make one good one, (parts are not sold, key parts)
this will not get better in time, IMO

[fixkick]

the ecu has 3 modes (major)
normal,
limphome (suzuki failsafe)
backup
the backup mode only , no flash codes. no DTC'S to read, due to the IM DEAD fact.
DTC = diagnostic Trouble codes, like code 41, lost spark.