these old ECU, all inputs are well protected ! series resistors and noise caps.
the outputs do not have any protection at all, (until modern aged cars and smart outputs are born)
it is just and open collector or open drain transistor to drive all things, like relays, VSV, injectors and spark coils.
never hot wire any outputs of any computer made if savvy is the game. do not.
do not short the 5vdc wire of the ECU output to ground or to 12vdc. or boom.
we call this in electronics, letting the smoke out, with a wide grin........
some ecu's for sure 8v just have a diode there (PCB) on the main relay coil to ground to turn it on.
this is so they can add other controls on this pin for say anti-thieft used in other market here.
what you find on that pin IDK, but is blown up. (fuses good)
i never did the J18 ECU ever. and are super rare cars now and even then.
I did this on g16 8v and 16v; yes
most are caused by others hotwiring good ECU. and blews up these parts easy as pie.
8v:
https://fixkick.com/ECU/transistors.html
G16b 16v main relay coil is activated by ECU DIODE D102. J18 IDK.
16v pins.
https://fixkick.com/ECU/16v-ecu-pins.html
sorry never did this for J18, ECU not easy to find nor the car. nor ever any j23 seen.
but using ohm meter with it set to buzz continuity mode finds the device that runs that pin, to main relay.
the European cars have anti-theft box, with 1 serial comm wire to the ECU and the ECU as transistor to main relay coil
the Anti-theft box tells the ECU OK to run engine and the transistor there turns on and main closes.
this I tell you, because some cars have the wrong ECU in them.
both the FP relay and The main relay coil outputs on the ECU can be blown up easy. doing hotwiring.
Im guessing your car is USA stock but has newer j23, long block only???? we have j18 sport with J20 engines too , no mods electric..
the outputs do not have any protection at all, (until modern aged cars and smart outputs are born)
it is just and open collector or open drain transistor to drive all things, like relays, VSV, injectors and spark coils.
never hot wire any outputs of any computer made if savvy is the game. do not.
do not short the 5vdc wire of the ECU output to ground or to 12vdc. or boom.
we call this in electronics, letting the smoke out, with a wide grin........
some ecu's for sure 8v just have a diode there (PCB) on the main relay coil to ground to turn it on.
this is so they can add other controls on this pin for say anti-thieft used in other market here.
what you find on that pin IDK, but is blown up. (fuses good)
i never did the J18 ECU ever. and are super rare cars now and even then.
I did this on g16 8v and 16v; yes
most are caused by others hotwiring good ECU. and blews up these parts easy as pie.
8v:
https://fixkick.com/ECU/transistors.html
G16b 16v main relay coil is activated by ECU DIODE D102. J18 IDK.
16v pins.
https://fixkick.com/ECU/16v-ecu-pins.html
sorry never did this for J18, ECU not easy to find nor the car. nor ever any j23 seen.
but using ohm meter with it set to buzz continuity mode finds the device that runs that pin, to main relay.
the European cars have anti-theft box, with 1 serial comm wire to the ECU and the ECU as transistor to main relay coil
the Anti-theft box tells the ECU OK to run engine and the transistor there turns on and main closes.
this I tell you, because some cars have the wrong ECU in them.
both the FP relay and The main relay coil outputs on the ECU can be blown up easy. doing hotwiring.
Im guessing your car is USA stock but has newer j23, long block only???? we have j18 sport with J20 engines too , no mods electric..
http://www.fixkick.com