I'm looking for confirmation on how the 2002 PT Cruiser autoshutdown relay works and is wired. Here's my interpretation, tell me if I'm wrong. When the key is turned on or if attempting to start the engine, the computer looks for a signal from the crankshaft positon sensor. If it receives that signal, the computer then grounds the E2 cavity of the relay. The E4 and E5 cavity's of the relay are a constant hot from the battery. With the relay installed, the voltage automatically crosses over from the E4 cavity to the E2 cavity. Once the computer receives the signal from the crankshaft position sensor, this is with the key on or if attempting to start the engine, the computer then grounds the E2 cavity which then sends the battery voltage towhat ever is getting fed.Mymain concernis to make sure that by installing the relay, the voltage is suppose to automatically cross over from the E4cavity to the E2 cavity. If this is correct, then I'mOK. Thank you foryour support, Tommy.

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[IMG]local://upfiles/1097/38E30AFCDF4B4950A6670C3284A3826C.gif[/IMG]

 

E4 and E5 are the power feeds
E2 is the control which the pcm grounds
E1 is the output that the relay supplies
The asd when the key is turned on cycles for 3 seconds then shuts off untill the car is running then it will stay on for the duration of the car running.

 

Yes, I understand that. However,this is what's happening. With the relay removed, I'm getting battery voltage at the E4 and E5 cavity's, which is normal. Now when I install the relay, the voltage automatically crosses over from the E4 cavity to the E2 terminal. This is with the ignition switch in the off position. This means that the voltage is now at the C2 Pin 67 of the PCM. This is what I'm concerned about. Is this how the system is suppose to work? I know that with the key in the on or run position, the PCM looks for a signal from the crankshaft sensor, and if it does not receive that signal, the E2 terminal does not getgrounded by the PCM. Again, my concern is this,is the voltage suppose to travel all the way up to the PCM C2 Pin 67 terminal with the ignition switch off? I just need toknow if that ishow the system was designed to work. Iswitched out 3 different relays and got the same results. Thank you, Tommy.

 

yes it is suptose to do that

 

Ok, very good. I assumed that was how it worked, I just needed to make sure. With that said, I have been working on modifying howmy GM and Chrysler relayswere wired. I installed a Chevy 3.8 V-6 into my 2002 PT Cruiser, and I hired a company to fabricate a special engine harness for my application. I'm currently correcting all of the mistakes they made, which includes crossed wiring. They alsotried todesign the electrical system to have the Chrysler and GM relays work with each other. Thisdesign caused therelays tooverheat. So, this is the reason why I'm trying to modify the relay wiring, to correct the overheating problem. I'm trying to isolate the GM relays from the Chrysler relays and where possible, disablevarious functions of the Chryslerrelays that are not needed. The drawing below is pretty much where I'm at with the mod's. I have re-wired the GM Fuel Pump Relay. If you look at the bottom left side of the drawing, you will see the GM Fuel Pump relay. If you look atterminal 87 of the relay, you will see that it now feeds the Chrysler fuel pump module, and that the Chrysler fuel pump relay C1 terminalhas been cut and isolated from the fuel pump module. You will also notice that the Chrysler fuel pump relay C2 terminal has been cut and isolated from the Chrysler PCM C2 Pin 74 terminal. So now, with those changes made, the GM Fuel Pump relaynow feeds the Chrysler fuel pump module from the brown wire at terminal 87 of the GM relay. And the GM PCM C2 Pin 3 controls the relay. With the key on, I can hear the fuel pumpworking. What I'm also trying to accomplish here, is to isolate the Chrysler Autoshutdown relay terminal E2, from the GM Autoshutdown relay terminal 87. This is so I can control the GM Autoshutdown relay fromthe GM side of the harness. However, now when I attempt to cut and isolate the dark blue/yellow wire where the red circle mark is located between the E2 cavity and the 87relay terminal,the fuel pump does not get activated.At this point,I can't figure out why? Any suggestions or thoughts will be appreciated. Thank you, Tommy.[/align][/align]

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I have added another updated attachment drawing. This may give you a better view of how the system is wired. Thank you for your support, Tommy.



[IMG]local://upfiles/1097/95B5BD9438A94AE2AE03D1A1DDD4787F.jpg[/IMG]

 

I'm currently re-wiring the GM and Chrysler relays. When completed, the relays will be totally isolated from each other. Thank you for your support.

 

Thanks again! Knowledge is power, and I'm getting enough here to edge up to 220 volts. LOL

Cheers,
Princess [sm=smiley34.gif]