Hello

I have a problem with ground to my ECU.
All grounds are good when ignition is off, but when I turn ignition on I measure 170 ohms on pin D1 and D6 and also the aldl-ground.
D7 is good at all times.

What can cause this problem?

FYI, the ecu was fried on all ground-pins before so I have replaced the ECU with new memcal and eeprom but it still doesnt work.
I canīt enter diagnostic mode to flash fault codes. I canīt connect with aldl-cable and laptop.
SES-light is always on and the engine runs like crap.

When I ground pin E8 the fan-relay switches but no fan comes on. (I have replaced the relay but no difference)
The heavy duty cooling fan relay works and the fans run when I use a jumper to force the relay to switch.

Itīs a 7730 ECU and the car is a Camaro 350 auto 1991.

I am from Sweden so excuse me if my English is bad

/Eric

 

I would start by checking the c100 connector (near the brake booster) for lose, dirty contracts and make sure the ground cable between the passenger side head and the bulkhead is tight and clean.