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FSM pinout wrong? fixing P0243 in an 05

2523 Views 12 Replies 4 Participants Last post by  khnitz
I have to error codes on my truck (a 2005 Ram2500) - P0243 and P0480. This summer, I replaced the wastegate solenoid, and the fan clutch wiring had to be re-worked because it got caught in the fan blade (that was the resultof a repair I had a shop do to replace the fan clutch the previous summer - the wiring worked its way into the path of the fan blade).

I still have both error codes, and the shop will still warranty the work on the fan clutch to correct the P0480 code, but I wanted to be sure there wasn't a complication from the wastegate solenoid that was a contributing factor.

Yesterday, I stepped through the wastegate solenoid P0243 diagnostic procedure from the FSM. I traced and verified every step of the path from the wastegate solenoid connector back to the fuse block (this is an '05, so it should be PRE-TIPM - it should not have the complicated TIPM from the '06 and later trucks).

When everything is assembled, I cannot measure from the fuse location (36) to the pin on the wastegate solenoid. However, I can measure a connection from the wastegate solenoid to the C5 connector (its Blue, not Black as the FSM states) and its pin 25 (not pin 26, as the FSM states). I can also measure a short from Fuse 36 to the C5 pin 25 socket on the fuse block. BUT, when everything is connected, I do not get a measurement from Fuse 36 to the wastegate connector pin. I unwrapped everything in the wiring loom alongside the battery, between C5 of the fuse block and C130 - what I found was a continuous wire for that length, too, which surprised me as the FSM says there should be a splice (S140) in that path.

I'm stumped...
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My skills are up to the task, but the FSM does not match the physical reality of what is in the vehicle. That last stretch of the connection between the wastegate solenoid and the fuse block is the mismatch (see image).

The truck has not been modified, so I am dealing with the from-the-factory wiring.


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Was using a volt/ohm-meter - I need to get a test light, too.
Sorry for the delayed feedback on this one. I got back into the truck tonight to check and straighten things out before dropping the truck off at the shop to have the A/C Fan Clutch repaired (and likely replaced) under their warranty.

With C5 disconnected, and Fuse 36 removed, I tested the connection through the IPM to its connector pins. The load side of Fuse 36 connects to C5-26 AND C5-25. Both wires are Gray/Pink (GY/PK). The FSM does not show C5-25 as populated, though it is electrically tied to C5-26, too. C5-26 powers the HVAC panel - in particular the switch and backlighting for the A/C and Rear Defogger switches.

The connection to the wastegate solenoid is verified, and the truck is now waiting at the shop. Hopefully once they replace the A/C fan clutch, this will clear the P0480 and P0243 (and P0483 showed up recently, too).
Thanks for the link to that video. That was one of the ones I reviewed when I first started digging into the issue. Fortunately, I do not have any chafing of the wiring (I wasn't blowing fuses, either - just throwing the codes). Same thing down at the wastegate actuator - no wiring issues there, either.

I'll post feedback after the shop is done with it.
To close this thread out, the shop found that the wiring to the Fan Clutch was also chafed at the aluminum guide that comes out and down from the Fan Clutch. The shop replaced the Fan Clutch (under their repair warranty), and I am free of error codes, now.

BUT, I now hear a noise when on the throttle starting around 2000 RPM and up. It's sort of like an alternator whine through the speakers (but it's not), and sort of like the sound you get when you use a blade of grass as a reed between your thumbs and blow. I'm wondering, now that the P0243 code is cleared and maybe my new wastegate actuator valve is working, if the noise is due to the cheap actuator valve I installed. Otherwise, there is something wrong with how they installed the new Fan Clutch, because that noise was NOT there before. I will start a separate thread here in the forum to figure that one out (after some searching).
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