so when I pulled the prom, (I guess to be correct the prom carrier) out of the ecm I didn't pay attention to which way it was in there. so my quetion is which way does it plug back into the ecm? I guess I should add it is the 730 ecm for tpi

 

The little notch on the top of the chip goes to the left when you're holding the ECM with the access panel at the bottom. In other words, the notch goes on the opposite side of the ECM as where the wiring harness cables connect to the ECM.

Does that make sense?


- Vern

 

got a pic?

 

i put mine in backwards a couple times. no damage occurred BUT that may not be true for you. i have a 7747 and assuming the wires enter the top of ECU the notch is to the right...not sure if your ECU is different

 

I just realized, I was talking about an individual chip inside a memcal adapter, my bad, sorry.

Probably/If you're talking about the entire memcal (blue topped thing about 3 inches long), with two holes/sight windows where you can see uder the blue cover. One hole will show a black chip with a probably silver sticker that has some letters on it (like "AUJP") and the other hole will show some blue and white lookind circuitry. The hole with the black chip/AUJP sticker goes one the side of the ECM away from the wiring harness connectors.

Here's a picture that shows what I'm talking about as a memcal. It's oriented like it would be installed if the wiring harness connectors are on the right and the chip opening on the ECM is closest to your belly while you hold the ECM in your hands.

Does this clear it up for you?

 

If you look really close at the underside (connector pin side) of the MEMCAL, you'll note that there are three raised portions in the plastic (two on one side, near the ends; and one in the center of the other side) that "key" into corresponding slots in the ECM's MEMCAL receptacle.

Those notches should make it at least a little difficult (although certainly not impossible) to install the MEMCAL backwards.

Take a look, it should be obvious.