95-96 MPI Relay diagnostic test procedure?

[krisj144]

Since the 95-96's are different than the 1g's or late 2g's, could someone provide me with the information about how to test this MPI relay to find out if it's bad or not?

I have the DSM CD and it doesn't seem to provide information about how to test the 95-96 relay though it does say for the later 2g's. The harnesse are different though so that information isn't of much use.

 

[Doug99RS]

I see the car under your s/n is a 1g. Are you trying to diagnose a problem on a 2g or convert something over? Do you have fault codes on a 2g and suspect a relay failure? Most relays are fairly simple. There's two paths for current to flow. One is the circuit that "makes" the relay. This uses a simple trigger voltage to "make" another circuit complete. The other circuit is the "Made" circuit. It will frequently carry more current than the other and supplies current to another component. What this does is allows the computer to work with lower amperage to reduce heat and increase longevity. I'm currently trying to dig up some wiring diagrams.
Doug

 

[krisj144]

Correct, I'm trying to fix a problematic 2g TSi that I have. First I thought it was the CAS, then the ECU, then the wiring harness, now I'm hoping it was the MPI relay all along.

I do understand how relays function, but this sucker has 8 terminals and they are not located like a typical relay where you have a ground, the common, and the two switched sides of the relay. I'm guessing I'll need to connect one of the terminals to 12V, another to ground, and then check the continuity between a couple of the terminals or something like that, but I just don't know.

Thanks for your help, I have exhausted my usual resources (shop manual, DSM cd, friends) already.

 

[Doug99RS]

Kris, I'm not having any luck. All of the diagrams I have are for the 2gnt. Even the factory wiring diagrams from Chrysler that I have borrowed don't show ANYTHING that is 4g63 specific. Everything's 420A. I'll keep looking but I'm scraping the bottom of the barrel at the moment.
Doug

 

[krisj144]

thanks man, I appreciate it, because I'm coming up with nothing too.