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3.9 ISB 170 Wiring Harness/ECM Help

184 Views 5 Replies 5 Participants Last post by  char1355
I have got my hands on a gorgeous 2001 3.9l ISB 170 4bt common rail attached to an Allison 1000 with only 80k miles on it! But the wiring harness and ECM were stolen. I can't for the life of me find on these forums....

Where can I find am Engine side wiring harness and/or ECM?
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I would try to source the engine harness from Cummins. For an ECM, you might try a heavy duty salvage company like LKQ Truck parts. Good luck!
Well, there are a couple of wiring harnesses you will need in addition to the ECM. Not positive but the transmission control module may be part of the engine one or separate. Another thing, better have some smelling salts on hand. These parts are not cheap. May cost you more than you paid for the engine. Here are some of them. I say some because Cummins only provides the ones for engine operation. You may need to contact an end user like Freightliner to get some of the wiring. Even the accelerator pedal is electronic.
First off is the engine control module (ECM). That is part #16 in this diagram. This also shows all the various sensors mounted on the engine. Part #16 is Cummins number 4899685. That part shows to be not available. Not a good beginning to the search. You may have to contact Cummins with your serial number to get the ECM. Price on those parts used to range from around $2000 to over $5000. There are companies who rebuild those and they usually charge around $1200.

In combination with the ECM there is also a cooling unit for that part. Cummins part 4897682 which is serviced as part 4025104. That little part may cause heart failure if it is missing. Cummins price $1712.24. Here is the diagram for that part. That price is just for part #5.

Here is the diagram for the main ECM wiring harness that links it to all those sensors. Original part number was 4897696. Last update shows part 3969064. All these part numbers show to be obsolete with no replacement. Sounding worse be the minute. There is a harness 4897696 for sale on ebay for $169.72. Cummins 4897696 Harness,Wiring | eBay I'd say that is the bargain of the century. Seems like the original price of that part was like $1500.

Wiring for the transmission, engine gauges, and accelerator etc. will have to come from someone like Freightliner. These prices I've listed are just for the main part item. Does not include any of those small parts. This is why you generally avoid one of these engines which is missing the wiring.
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It might be worth your time to consider selling the Allison and installing a 47rh which requires no accessory computer at all. Your decision would consider intended use, cost and time frame of a complete Allison up and running vs. 47rh up and running, physical space in your vehicle, time frame to get operational, and so on.

Ed in CO
Ed, the 47RH won't bolt to an ISB 170. It uses SAE3 mounting. The Allison 1000 was the only transmission available in this country. In Europe there was also a ZF manual offered be we don't see that one here. The mention of doing a P pump is fine but you're talking about a lot of money. May be close to $10,000 depending on how cheap you can get the P7100. A lot involved in that change over. Requires a special front gear housing which costs $1545. Then you need a new crankshaft and cam. Everything on the ISB 170 is on the rear and has to be moved to the front. Then you'll need new injectors and custom fuel lines. Will need a custom oil pan. Standard 4bt pan won't work. There will be lots of misc parts like lift pump and plumbing and rear crank seal. Have to remember that the P7100 conversion is mainly aimed at the Dodge ISB engines which are front gear train where the ISB 170 is rear gear train.
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