P2509 Code

[BigCountry73]

Hello all,

I have a 2007 that decided to throw a P2509 code this morning. I went to start it like normal. The truck shook for a second and then it through the code. I checked both batteries this evening with a voltmeter and it shows 12.57 on driver's side and 12.54 on passenger side. This is with truck off. I started the truck and measured and it shows 14.67 and 14.64 which I'm assuming is good while running.

What can I do to try to troubleshoot the issue? I noticed the 50-pin connector has a couple of B+ terminals and some grounds. I'm thinking check there to see if I'm getting proper voltage? Possibly check grounds? I wanted to replace the battery cables eventually along with the batteries, but I'm not sure that's the issue at this point.

Any advice?

Thanks in advance.

 

[Darkbloodmon]

Check and clean grounds is a good first step, Here is pic of the ECM ground location. There could be multiple ECM grounds, this is just one I noticed when I was cleaning connections and installing new cables after the OEM alternator went out on me.

 

[Timd32]

Good suggestions to check the wiring and connections.

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The 6.7 documents had some better detail then the 5.9 and it could work differently for sure between them so don't substitute based on any of the attached.

Plus just pushing paper your way no hands on for this. My personal solution is usually buy a new truck or take this one apart so far where it may never run again, and you lose track of why it was you started down this road.......

Becareful extra careful working with ECM and in general computer harnesses and any sub par meters and devices to verify said wiring.

There were some cool intermittent procedures that cover the basics not specific to this exact code just sharing because they might help.

Repairs that fixed this were listed as the normal, batteries, battery cables, wiring issues... there were 4 or 5 verified repairs with those as answers.

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Truck RAM 2500 Truck 4WD

L6-6.7L DSL Turbo VIN A

6.7L Diesel

• Vehicle
• ALL Diagnostic Trouble Codes ( DTC )
• Testing and Inspection
• P Code Charts
• P2509
• 6.7L Diesel

6.7L DIESEL
P2509-ECM/PCM POWER INPUT SIGNAL INTERMITTENT

For complete wiring diagrams refer to Diagrams/Electrical.


Theory of Operation

The ECM receives a constant voltage from the batteries through the unswitched battery wires that are connected directly to the positive (+) battery post. The ECM receives switched battery input through the vehicle Ignition Switch wire when the vehicle is turned on. The ECM will illuminate the MIL lamp immediately after the diagnostic runs and fails. During the time the customer may experience some performance effects such as engine dying or hard starting. Fault information, trip information could be inaccurate. The ECM will turn off the MIL lamp after the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:

Continuous - key on or key off.

- Set Condition:

Loss of voltage detected at the ECM for a calibrated amount of time. Supply voltage to the PCM fell below 6.2 volts momentarily or the ECM was not allowed to power down correctly (retain battery voltage for 30 seconds after key off).


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2007 Dodge or Ram Truck RAM 2500 Truck 4WD

L6-5.9L DSL Turbo VIN C

5.9L Diesel

• Vehicle
• ALL Diagnostic Trouble Codes ( DTC )
• Testing and Inspection
• P Code Charts
• P2509
• 5.9L Diesel

5.9L DIESEL
P2509-POWERDOWN DATA LOST ERROR

For complete wiring diagrams refer to Diagrams/Electrical.


- When Monitored:

Continuous - key on or key off.

- Set Condition:

Loss of voltage detected at the ECM for a calibrated amount of time.