Engine/Transmission (1998.5 - 2002) 2001 24V no start — electrical power issues

[Sticks]

In one of your emails...

Of the three connectors on the PCM, one of them does not latch in; it pulls out easily. The other two have working latch mechanisms.

This could definitely be the source of your issues, or at least a heavily contributing source. Take a close look at the connector for bent pins, and any female ports that may be widened. Look for any indications of heat (discoloration) on the pins.

Try to find a way to get that connection locked in (zip tie). It may come down to having to try to find a replacement connector.

Is the lock tab still on the connector and/or the PCM?

Is there a weather seal (rubber gasket thingy)? Sometimes the weather seal can get bound up preventing a connector to lock in. Use some dielectric grease (spit works in a pinch) to lube up the seal then connect.

 

[Gordon Maney]

In one of your emails...



This could definitely be the source of your issues, or at least a heavily contributing source. Take a close look at the connector for bent pins, and any female ports that may be widened. Look for any indications of heat (discoloration) on the pins.

Try to find a way to get that connection locked in (zip tie). It may come down to having to try to find a replacement connector.

Is the lock tab still on the connector and/or the PCM?

Is there a weather seal (rubber gasket thingy)? Sometimes the weather seal can get bound up preventing a connector to lock in. Use some dielectric grease (spit works in a pinch) to lube up the seal then connect.

I looked more closely at it and the very point of the latching clip is broken off. It seems to press in all the way nicely. I will look more closely at its pins and receptacles.

My other remaining, general, question is..... if I have to guess, choosing either an ECM to buy or a PCM, do I choose an ECM, or am I still fearing that the PCM's control of the ASD relay is still a possibility?

 

[Sticks]

Go back to your original trouble code. No communication between the ECM and the PCM. One step at a time.

You just identified bad ground connections and a loose connector. Address those issues, then re-check the status of the code and see if the truck starts.

The last thing that you want to do is start throwing parts at the truck until the problem goes away.

 

[Gordon Maney]

Go back to your original trouble code. No communication between the ECM and the PCM. One step at a time.

You just identified bad ground connections and a loose connector. Address those issues, then re-check the status of the code and see if the truck starts.

The last thing that you want to do is start throwing parts at the truck until the problem goes away.

Good idea. I don't want to spend money I don't need to spend and don't really have anyway.

Question. That previous code will still be in there, won't it? It would have to be cleared with a scanner or other test equipment?

I might be able to borrow one today, if that is the case. My concern, as I understand all this, is that if I go out and try it again that code will still be stored. Is that right?

 

[Sticks]

Should be if you have not cleared it. To verify, you will need a scanner of some sort to clear the code, and start the vehicle (not that the code is preventing you from starting). If the code comes back after you clear it, you have not found the problem.

 

[Gordon Maney]

Should be if you have not cleared it. To verify, you will need a scanner of some sort to clear the code, and start the vehicle (not that the code is preventing you from starting). If the code comes back after you clear it, you have not found the problem.

If it would just start, that would be remarkable progress.

 

[JLandry]

My other remaining, general, question is..... if I have to guess, choosing either an ECM to buy or a PCM, do I choose an ECM, or am I still fearing that the PCM's control of the ASD relay is still a possibility?

Gordon,



That P1694 DTC originates from the PCM... it's the PCM saying it's not hearing from the ECM. When you consider that trouble code along with the other symptoms which you've described (i. e. : the ECM not energizing the fuel injection pump relay or the lift pump), the highest probability is that the ECM has failed and the PCM is fine.



When you've decided you're ready to start buying parts, I'd lean toward getting a refurbished ECM. Worst case if the ECM turns out not to be the problem, you'll have a spare... or you can sell it on eBay for close to what you paid for it.



Good luck,



John L.

 

[Gordon Maney]

I will be leaving here in a while to borrow an OBDII scanner.

... . and, although I don't want to have to buy an ECM, I consider possible vendors. Some of the vendors I find seem a bit questionable.

I found this one... .

Auto Computer Systems - quality ecu, ecm, & ecc units

... . offering lifetime warranty described here:

Auto Computer Systems - quality ecu, ecm, & ecc units

I also find... .

Auto Computer Exchange - Auto Computer Superstore - Cheaper than dealers and mechanics.

... . and they are having a special price on the Dodge Cummins ECM I would need for $595. They way the conversation went, it somehow made me nervous. Reputable?

and

Ford GM ECU ECM PCM TCU Lexus Toyota Honda Acura repair used Mitsubishi

That one offers quite a bit of background information which may be useful, though I admit to not being qualified to evaluate it.

They will also repair/rebuild yours for $450, or exchange you one for $695. The repair of yours may take time not to exceed one week. The telephone presence of the person there was much better than the one I mention above that made me nervous.

... . off to get the scanner.

 

[JLandry]

I will be leaving here in a while to borrow an OBDII scanner.

Gordon,



You can buy a good basic code scanner for under $50, so it may be worthwhile to just buy one to keep in your toolbox. Any auto parts store will sell them, and Harbor Freight Tools, or even Wal-Mart sells them. All you need is a code scanner that will display and clear trouble codes. Unless you have money burning a hole in your wallet, don't waste your money on versions that feature a text listing of the trouble code title, multiple languages, memory, etc. Once you have the trouble code number, you can easily look up the meaning on the Internet and here on the TDR forum.

... . and, although I don't want to have to buy an ECM, I consider possible vendors. Some of the vendors I find seem a bit questionable.

That's funny... that $595 "special" Auto Computer Exchange in Florida mentioned isn't a special at all... it's their regular price they've always sold them for.



I've purchased both a spare ECM and PCM from Auto Computer Exchange BUT THROUGH THEIR EBAY LISTING and I had no problems with them whatsoever. When I did speak to them on the phone for some info beforehand, I too got an uncomfortable feeling.



They have a terrible BBB rating (an "F") and a quick search here on the TDR forum and Google will turn up both complaints and praise for them. Seems as though they'll do anything to land a sale, but if something goes wrong after the order is placed, they're difficult to deal with. But they're significantly less expensive than other places. Doing business with them could be a gamble.



If you decide to purchase from them, I'd highly recommend you order from one of their eBay listings (search for Dodge Cummins ECM), that way you have some recourse (from the threat of negative feedback) and the assistance of eBay if they don't hold up their end of the deal. Interestingly, they have a great feedback rating on eBay... apparently they value keeping that sales outlet open.



Good luck,



John L.

 

[Gordon Maney]

Gordon,

You can buy a good basic code scanner for under $50, so it may be worthwhile to just buy one to keep in your toolbox. Any auto parts store will sell them, and Harbor Freight Tools, or even Wal-Mart sells them. All you need is a code scanner that will display and clear trouble codes. Unless you have money burning a hole in your wallet, don't waste your money on versions that feature a text listing of the trouble code title, multiple languages, memory, etc. Once you have the trouble code number, you can easily look up the meaning on the Internet and here on the TDR forum.

That's funny... that $595 "special" Auto Computer Exchange in Florida mentioned isn't a special at all... it's their regular price they've always sold them for.

I've purchased both a spare ECM and PCM from Auto Computer Exchange BUT THROUGH THEIR EBAY LISTING and I had no problems with them whatsoever. When I did speak to them on the phone for some info beforehand, I too got an uncomfortable feeling.

They have a terrible BBB rating (an "F") and a quick search here on the TDR forum and Google will turn up both complaints and praise for them. Seems as though they'll do anything to land a sale, but if something goes wrong after the order is placed, they're difficult to deal with. But they're significantly less expensive than other places. Doing business with them could be a gamble.

If you decide to purchase from them, I'd highly recommend you order from one of their eBay listings (search for Dodge Cummins ECM), that way you have some recourse (from the threat of negative feedback) and the assistance of eBay if they don't hold up their end of the deal. Interestingly, they have a great feedback rating on eBay... apparently they value keeping that sales outlet open.

Good luck,

John L.

On the phone, the woman emphasized that price as a special price now being offered.

This group allcomputerresources.com has a good phone presence.

I don't doubt your thinking on the ebay approach, but I have never purchased anything there and do not have a paypal account. So, should I need an ECM, I think I would need to take a different approach.

Thank you for your scanner advice; it is good.

 

[JLandry]

On the phone, the woman emphasized that price as a special price now being offered.

Sounds just like a car salesman.

This group All Computer Resources Dodge Jeep Chrysler Ford GM OEM Engine Computer Auto Computer PCM ECM ECU TCM TCU Store has a good phone presence.

Well they have a very impressive D+ rating on the BBB web site and the complaints I found through Google make them sound exactly like Auto Computer Exchange. Read this one on Ripoff Report

I don't doubt your thinking on the ebay approach, but I have never purchased anything there and do not have a paypal account.

Maybe now's a great time to sign up? I've been using eBay since 1997 and Paypal about the same time.



John L.

 

[Gordon Maney]

The ECM ToGo place did not have any reports listed.

Here is another ECM Depot - About Us

 

[Gordon Maney]

A new development, odd as it may be. I connected my borrowed Actron CP9135 scanner and it won't connect. I get a link error.

I had successfully used this very scanner a couple of months ago as part of this diagnosis. It only gave me the same codes the odometer gave me, but it did link and read. It gave me the 1694 code then.

Now it won't link. What does that mean? All components are connected. The differences are that now I have a different injection pump and a cleaned ground at the PCM.

 

[JLandry]

Now it won't link. What does that mean? All components are connected. The differences are that now I have a different injection pump and a cleaned ground at the PCM.

It could mean the ECM is indeed dead... or maybe it's not receiving power? Verify that the 20 amp fuse #3 located in the PDC (Power Distribution Center on the driver's side fender under the hood) isn't blown. You may also want to verify 12 volts is present between this fuse and a good engine ground using your test light or voltmeter.

What happens when you check for trouble codes in the odometer window? In case you're not familiar with the procedure: Be prepared to write down anything you see in the odometer window, then turn the ignition key ON-OFF-ON-OFF-ON

John L.

 

[Gordon Maney]

It could mean the ECM is indeed dead... or maybe it's not receiving power? Verify that the 20 amp fuse #3 located in the PDC (Power Distribution Center on the driver's side fender under the hood) isn't blown. You may also want to verify 12 volts is present between this fuse and a good engine ground using your test light or voltmeter.

What happens when you check for trouble codes in the odometer window? In case you're not familiar with the procedure: Be prepared to write down anything you see in the odometer window, then turn the ignition key ON-OFF-ON-OFF-ON

John L.

I have checked that fuse with an ohmmeter, but not a voltmeter at that location. The odometer gives me the 1694 code.

I will try the voltmeter test, probing the terminal with the fuse removed, I presume? Since the terminals are not accessile with the fuse in place.

 

[JLandry]

I will try the voltmeter test, probing the terminal with the fuse removed, I presume? Since the terminals are not accessile with the fuse in place.

Yes.



If you find 12 volts are indeed present on one side of the socket for fuse #3 in the PDC, and you've verified the fuse is good, then reinstall the fuse and perform the following checks:

1. With the ignition switch OFF, disconnect the 50-pin connector from the ECM.

2. Using your voltmeter (or a test light), verify 12 volts are present at socket numbers 48 and 50 of the ECM's 50-pin connector. Use a straightened paper clip inserted into the socket if your voltmeter probe is too wide to enter and make contact down in the sockets. These two sockets are supposed to provide 12 volts to the ECM at all times (when the vehicle batteries are connected obviously).

3. Next turn the ignition key to the RUN position.

4. Again using your voltmeter (or a test light), verify you have 12 volts present at socket number 5 of the ECM's 50-pin connector. When 12 volts appear at this socket, the ECM turns on.

5. Turn the ignition switch OFF and reconnect the ECM connector.​

If these checks pass successfully, then it's pretty safe to assume the ECM is toast. If any of the checks don't pass, then you probably have a wiring problem which you'll need to investigate further.



Please keep us posted.



Good luck,



John L.



#ad

 

[Gordon Maney]

I will do these things later this morning.

 

[Gordon Maney]

Yes.

If you find 12 volts are indeed present on one side of the socket for fuse #3 in the PDC, and you've verified the fuse is good, then reinstall the fuse and perform the following checks:

1. With the ignition switch OFF, disconnect the 50-pin connector from the ECM.
2. Using your voltmeter (or a test light), verify 12 volts are present at socket numbers 48 and 50 of the ECM's 50-pin connector. Use a straightened paper clip inserted into the socket if your voltmeter probe is too wide to enter and make contact down in the sockets. These two sockets are supposed to provide 12 volts to the ECM at all times (when the vehicle batteries are connected obviously).
3. Next turn the ignition key to the RUN position.
4. Again using your voltmeter (or a test light), verify you have 12 volts present at socket number 5 of the ECM's 50-pin connector. When 12 volts appear at this socket, the ECM turns on.
5. Turn the ignition switch OFF and reconnect the ECM connector.​

If these checks pass successfully, then it's pretty safe to assume the ECM is toast. If any of the checks don't pass, then you probably have a wiring problem which you'll need to investigate further.

Please keep us posted.

Good luck,

John L.

#ad

Fuse #3 is good. I removed it, touched each of the two terminals with which it engages and one was hot, as evidenced by my test light. I tested that fuse with an ohmmeter, and also exchanged it with the 4-way flasher fuse. The flashers work with the fuse removed from position 3

I do not get my test light to signal when connected to either of terminals 48 or 50, with the key off.

Key on, I get it to light with terminal 5. That said, the terminal that lights is position 5 if your drawing is the terminal array as viewed from the driver's side fender, rather than holding the connector in your hand and viewing the business/engaging side of it.

Keeping that in mind, I used the driver side fender perspective and tried 48 and 50 again; still dead. I don't believe I have any difficulty getting into those terminals with my test light, but I am going to try your paper clip approach, just to be sure.

So, if 48 and 50 are dead, but 5 is OK, what does that mean?

Here I thought I was about to buy an ECM, but now that is certainly in question.

 

[JLandry]

So, if 48 and 50 are dead, but 5 is OK, what does that mean?

It suggests that there could be a break in the wiring somewhere between fuse #3 in the PDC and the ECM connector. You'll have to troubleshoot the wiring harness by checking for 12 volts at various points along the circuit until you find where it stops.



See the attached schematic from the Dodge service manual of the circuit which runs from the battery all the way to the ECM connector. Since you've already verified you have power at fuse #3 in the PDC, you can start your search after that point. Also, since you don't have power at either socket #48 or #50 at the ECM connector, it's probably safe to assume the break is before splice 167 (listed as S167 on the schematic). So by process of elimination, the break will most likely be between fuse #3 in the PDC and splice 167.



The suspect culprits for a break location are joint connector #2, which is inside (under) the PDC, connector 130 (listed as C130 on the schematic), splice 161 (S161), and connector 125 (C125).



I'd recommend beginning your search toward the ECM end of the circuit and work back from there. Note that according to the schematic, the wire in this entire circuit is Red with a White stripe. Keep this is mind when you're trying to find the correct pins to check on the connectors.

S167 is located in the wiring harness bundle after C125 adjacent to the lift pump on the side of the engine (if you have one). I'd skip worrying about finding this splice (unless you have to later) and move on to C125.



C125 is an 11-pin connector located on the firewall at the rear of the engine. You're looking for pin #3 there. A pinout diagram is attached. Keep in mind the mirror image issue you've already learned about when reading pinout diagrams. I'd check to see if power is present at the PDC side of this connector by disconnect it, or by back probing the connector using a paper clip inserted alongside the wire where it enters the connector. If you find power here, then the break must be further up the circuit toward the PDC.



Next comes S161, which is located in the wiring harness bundle leading between the PDC and C125. As before, I'd skip worrying about this splice for now and move on to the next connector in the circuit.



C130 is the large squarish shaped 42-pin connector located in the right rear corner of the PDC after you take the cover off. According to the schematic, you're looking for pin #3 there also. A pin diagram is attached. Disconnect C130 and test to see if you have power at pin #3 on the PDC side. If you do, you'll have verified joint connector #2 inside the PDC is fine. Reconnect C130 and try back-probing pin #3 with a paper clip to see that power is getting through the connector.​

Please let us know what you find.



John L.

 

[Gordon Maney]

Regarding C130, I had been studying it prior to reading your post. Is that disconnected by loosening the capscrew [displaying a phillips screwdriver feature] visible from above?

Regarding the joint connector 2 under the PDC, that would be visible by removing fasteners that hold down the PDC?