New Problem ( Fuel pump keeps running with the key out )
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Joined: Jun 2019
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No. A couple of caveats before inserting my opinion. I adapted this information for Ram 1500 using a Mitchell wiring diagram. And one of the wires in the instructions was in a different location on the connector.
The relay only operates the fuel pump and receives a turn on signal (ground) from the PCM. Power is feed to the relay via a new fuse circuit being added.
Your issue appears to a bad ground. Viewing a ground distribution circuit diagram for a Ram pin 34 (C1), it doesn't supply a ground to any engine control circuits, not to be confused from were pin 34 (C1) receives its ground. This may explain the massive overload on that pin that you encountered. My suggestion is to locate the body ground and check for excessive resistance. From what I can tell once you correct this your vehicle should run. The bad news is that it won't shift one of the relays it supplies a ground to, is for the transmission. The other grounded relays are for door locks and the windshield washer pump.
This body ground point is a major supply a ground circuit for the PCM and the O2's. It possibly explains why that pin looks like it was used for arc welding. The grounds were probably back feeding through the deceased pin.
Good luck
The relay only operates the fuel pump and receives a turn on signal (ground) from the PCM. Power is feed to the relay via a new fuse circuit being added.
Your issue appears to a bad ground. Viewing a ground distribution circuit diagram for a Ram pin 34 (C1), it doesn't supply a ground to any engine control circuits, not to be confused from were pin 34 (C1) receives its ground. This may explain the massive overload on that pin that you encountered. My suggestion is to locate the body ground and check for excessive resistance. From what I can tell once you correct this your vehicle should run. The bad news is that it won't shift one of the relays it supplies a ground to, is for the transmission. The other grounded relays are for door locks and the windshield washer pump.
This body ground point is a major supply a ground circuit for the PCM and the O2's. It possibly explains why that pin looks like it was used for arc welding. The grounds were probably back feeding through the deceased pin.
Good luck
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Joined: Jun 2019
Posts: 5
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As mentioned before the diagram I used is for a Ram 1500 were there are similarities it's possible just enough to get you into bigger trouble. You would best be served by purchasing a subscription for your vehicle. The web site that I used is https://www.eautorepair.net/Marketing/Default.asp but there are others that work well such as Alldata. For a one year subscription you will be money ahead. You'll also be able to look up any TSB's that might be on your vehicle. When the going gets deep one of these two and Idnetifix are used to trace circuit problems. The link attached should get you through to a solution.
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Joined: Mar 2023
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From: Texas
2012 ram 1500 5.7 hemi power draw
If you're wanting to diagnose this, the first thing I'd do is see if you have voltage across fuse M25 (20A) in the TIPM when the key is Off. If so, then you need to determine if the TIPM is getting signal to activate the fuel pump relay or if the issue is the fuel pump relay within the TIPM. Still with the key off, check for battery voltage across fuse M33 (10A) in the TIPM. That fuse should only have power when the key is in Run or Start. If you have power on this fuse with the key Off, post back with that result as it will take some interesting diagnosis.
Assuming you don't have power across fuse M33 with the key Off, then check for power and ground at wire A40 in the C1 connector to the TIPM. This could be a bit tricky to measure, but this is the trigger from the PCM to activate the fuel pump relay. Unfortunately, I cannot really tell from the wiring diagram if this should be power or ground to trigger the relay. Standard convention would suggest this signal will be pulled to ground to activate the relay, but I'm not 100% positive on that. I may have to do some more digging to see if I can get confirmation on that.
-Rod
Assuming you don't have power across fuse M33 with the key Off, then check for power and ground at wire A40 in the C1 connector to the TIPM. This could be a bit tricky to measure, but this is the trigger from the PCM to activate the fuel pump relay. Unfortunately, I cannot really tell from the wiring diagram if this should be power or ground to trigger the relay. Standard convention would suggest this signal will be pulled to ground to activate the relay, but I'm not 100% positive on that. I may have to do some more digging to see if I can get confirmation on that.
-Rod
Last edited by Joesoldram; Mar 28, 2023 at 04:38 PM. Reason: Adding information
