robbynne

There have been lots of posts and questions here regarding a myriad of problems, primarily trailer lighting related, involving the Power Distribution Center (PDC) which, as we all know, is part of the Integrated Power Module, the other half of which is the Front Control Module (FCM). A few of you have asked about opening up the (sealed) PDC. Well, after having to replace my PDC with a salvaged one ($250.00, California ripoff ) because new ones are on nationwide backorder with no ETA, I decided to operate on my old one.

I opened it up today to reveal what we all knew was there; 3 Tyco Micro Power ISO relays, one each for the left and right trailer turn signals and one for the parking lamp relay control (even though there is an external relay (#73). The relays are soldered to the PDC printed circuit board and replacing any or all of them will be no problem to anyone with PCB soldering experience. However, the big problem is that no TYCO distributor reports any in stock; the item is an 83 day lead time item and the minimum order quantity is 480 pieces if I recall correctly. I have contacted the TYCO factory for help in locating these or an equivalent; but I am not holding my breath.

I did NOT open the Front Control Module (FCM) as mine was good and is back in the truck with the salvaged (but working) PDC.

If you would like any info regarding opening the PDC you may contact me at robbynnet@live.com. I would have posted photos with detailed instructions but my SO took the digital camera and has yet to return it . Hopefully, I will have photos and more info in a week or so.

regards

htgreen3

Great info, look forward to pictures and additional details. I hate it when manufacturers create these pieces and we are stuck with them.

Thanks

vzdude

Is there room to put a bigger relay in? Maybe with a few modifications? Are the relays soldered to the board? Come on with the pictures!

vzdude

Actually.....after thinking a little more.....could a person just solder a harness to the PCB and have the wires exit the PDC and then plug into a larger relay like the ones that plug into the top of it? Could we make an add on PDC, so to say, to have those relays serviceable? That would be ideal IMO.

MikeyB

Post the details for the Tyco micro relays. I'll see if there's a cross reference with another vendor.

MikeyB

robbynne

The Tyco micro relay info is as follows (from the relay case markings):


Tyco

VFM 21F42-S01
0303712B

The Tyco order number I found in their on-line catalog is: 1432502-1

nsxt

Panasonic CM1A-P-12V Micro PCB relay looks like a match.

http://www.mouser.com/Search/Product...M2ZMu1mQ%3d%3d

http://pewa.panasonic.com/pcsd/produ...ech_eng_cm.pdf


On the IPM you took apart, are there diodes next to the relay coil terminals?

robbynne

I will check out the Panasonic relays. Thanks.

Next to the cluster of three (3) relays are two (2) positive power temperature coeffcient devices with radial leads (self resetting circuit breakers, if you would). They are PTC 2 (4.5a) and PTC 5 (7.5a). There is no manufacturer info but they look like Tyco or Bourns devices. There are two (2) more positions on the pcb for PTC's #3 and #4, but they are not populated.

GreyTD

What went wrong with yours? Did the relays burnup or is there something else burnt?

nsxt

If there are no protection diodes, for both the coil and output, then somebody at Dodge doesn't know how inductors work and that even a small inductor can create destructive EFT voltage, or that wiring = inductance.

Kinda makes me want to take mine apart and add a few diodes.

robbynne

Hello all-
After hours and hours of searching and help from NXST and some others, I have finally located a replacement Mirco ISO relay that some vendors ACTUALLY HAVE IN STOCK! These relays are DIRECT replacements for those on the PDC circuit board and will require no modifications. I have ordered six (6) of them and should have them next week. I will also have my digital camera back as well. I will just need to unsolder the defective relay from my PDC's circuit board and then solder the new one in its place. I will photograph the entire operation and discuss what is required to dis-assemble the PDC and re-assemble it. After I get my PDC back together, and my truck returns from a trip to Arizona, I will install the repaired PDC and ascertain if it works.
Stay tuned....

nsxt

part numbers? supplier?

MikeyT

I'm experiencing the trailer turn signal issue with my 2004. I replaced the FCM to no effect and now I am anxiously waiting Rob's update on whether the relay replacement works.

I've also got a used but apparently functional FCM lying around now.

robbynne

NXST-

The relays I have ordered are made by American Zettler in Aliso Viejo in California.

http://azettler.com/pdfs/az988.pdf

The part number I ordered is:

AZ988-1AT-12DSEC3R

American Zettler has some of these in stock; however, I ordered mine from:

RelayCenter.com

They cost $4.30 each, plus tax and shipping.

SOhappy

I think you'd basically be doing this:

https://www.dieseltruckresource.com/...hlight=trailer

Note that it didn't help me, because the problem on my truck appears to be in the FCM. If your issue is the relays then this method "should" work.