My John Deere decided to take some time off

[Komatsuvarna]

O C Diver, Was a resolution ever determined with this issue? Dealing with the same thing on the same engine.

 

[O C Diver]

O C Diver, Was a resolution ever determined with this issue? Dealing with the same thing on the same engine.

The ECM had become heat sensitive. Basically it would fail when the unit became too hot. The short term fix was to remove it from the engine block and tie wrap it to the wiring harness (away from the engine). The long term fix was to replace the ECM. This requires sending yours to John Deere or a dealer and having them remove your history and programming, and install it on a new ECM. That cost around $2K. In addition, I added spacers and heat conduction aluminum strips to dissipate the heat and prevent the engine from transferring heat to the ECM. A wiring harness may be available that allows the remote mounting of the ECM.

Below, the new ECM with spacers and aluminum heat dissipation strips.

Ted

 

[Komatsuvarna]

That's a good idea. I too wondered about the vibration and heat being that close to the engine. I like the mods! On mine, pretty much every time I started the engine it would throw the high resistance for the solenoid code. I changed the pump itself and it worked great for 13 hours and multiple starts. Yesterday it was intermittent. Today it was pretty consistent again with the same code. I ohmed the wires out and they are good. Im gonna replace the connector at the solenoid first. I really dont expect it to change anything. Then decide if I should do the ecm or if my reman Deere pump ( new is not available) is actually faulty. Yesterday momentarily I lost the oil pressure and coolant readings at the same time...I know I had oil pressure but those come from the ecm so Im leaning that way now. Thanks for the reply!

 

[Jeff F]

That's a good idea. I too wondered about the vibration and heat being that close to the engine. I like the mods! On mine, pretty much every time I started the engine it would throw the high resistance for the solenoid code. I changed the pump itself and it worked great for 13 hours and multiple starts. Yesterday it was intermittent. Today it was pretty consistent again with the same code. I ohmed the wires out and they are good. Im gonna replace the connector at the solenoid first. I really dont expect it to change anything. Then decide if I should do the ecm or if my reman Deere pump ( new is not available) is actually faulty. Yesterday momentarily I lost the oil pressure and coolant readings at the same time...I know I had oil pressure but those come from the ecm so Im leaning that way now. Thanks for the reply!

If you've replaced the pump and the connections are secure I'd say the ECM is the next step.

Make sure each pin connection is intact in the connectors. The pins can be pulled with a special release tool for close inspection.

 

[O C Diver]

That's a good idea. I too wondered about the vibration and heat being that close to the engine. I like the mods! On mine, pretty much every time I started the engine it would throw the high resistance for the solenoid code. I changed the pump itself and it worked great for 13 hours and multiple starts. Yesterday it was intermittent. Today it was pretty consistent again with the same code. I ohmed the wires out and they are good. Im gonna replace the connector at the solenoid first. I really dont expect it to change anything. Then decide if I should do the ecm or if my reman Deere pump ( new is not available) is actually faulty. Yesterday momentarily I lost the oil pressure and coolant readings at the same time...I know I had oil pressure but those come from the ecm so Im leaning that way now. Thanks for the reply!

Before you do anything else, I would remove the ECM from the engine and tie wrap it to the wire loom. This worked flawlessly for 4 or 5 months of cruising before I could replace the ECM at my local dealer.

Ted

 

[Nick F]

Re-reading OC Diver's original post, it would appear that the ECU is nothing more than an electronic governor (its only control output being the injection pump).

With a system like this using a mechanical injector pump it seems a pity that there is no provision for a "limp home" mode. If this was in my boat I would certainly be looking at how to manually take over the injector pump control. Obviously, would have to protect against overspeeding.

Am I missing something here?

 

[Komatsuvarna]

Re-reading OC Diver's original post, it would appear that the ECU is nothing more than an electronic governor (its only control output being the injection pump).

With a system like this using a mechanical injector pump it seems a pity that there is no provision for a "limp home" mode. If this was in my boat I would certainly be looking at how to manually take over the injector pump control. Obviously, would have to protect against overspeeding.

Am I missing something here?

Would be hard to do. Its not "hot" all the time...it basically fires in milliseconds from the ecu to control the fuel supply...although it may appear to have a low voltage on it all the time.

 

[Komatsuvarna]

Before you do anything else, I would remove the ECM from the engine and tie wrap it to the wire loom. This worked flawlessly for 4 or 5 months of cruising before I could replace the ECM at my local dealer.

Ted

It will give it a try, but i think mine may be worse than yours. It was cool here this morning. I cranked it up and less than 30 seconds had the code.

 

[Komatsuvarna]

If you've replaced the pump and the connections are secure I'd say the ECM is the next step.

Make sure each pin connection is intact in the connectors. The pins can be pulled with a special release tool for close inspection.

Basically what Im thinking too. I was convinced the pump was bad, then i noticed my oil pressure and coolant gauges on the low peg. I then scrolled through the diagnostic menu and those 2 were blanked out with no code for them. I restarted it and they came back to life. I then unplugged the wire from the individual sending units and the gauges fell to the peg, the diagnostic menu showed no data and It left a code for each then.

 

[Jeff F]

Am I missing something here?

I'll comment, as I educated myself extensively on this particular motor over 6 months as I tried to diagnose increasingly alarming symptoms...

You're not missing anything. But I think a solution that doesn't involve a functioning ECM isn't feasible. More modern motors do have 'limp home' modes, but AFAIK if the ECM powers down those features are lost.

If you read through Ted's issue, it wasn't the fault code that triggered the shutdown, it was the ECM powering down. That was my problem as well, and based on Komatsuvarna losing instrumentation it sounds very much the same.

In this motor the ECM controls both timing and duration of the pump. There isn't any way of manually controlling the pump.

 

[Jeff F]

Basically what Im thinking too. I was convinced the pump was bad, then i noticed my oil pressure and coolant gauges on the low peg. I then scrolled through the diagnostic menu and those 2 were blanked out with no code for them. I restarted it and they came back to life. I then unplugged the wire from the individual sending units and the gauges fell to the peg, the diagnostic menu showed no data and It left a code for each then.

Have you lost power at any point, or are you just getting alerts?

You might appreciate the document I sent Ted. It's very comprehensive and describes troubleshooting tests. PM me and I'll email it to you.

 

[Komatsuvarna]

Have you lost power at any point, or are you just getting alerts?

You might appreciate the document I sent Ted. It's very comprehensive and describes troubleshooting tests. PM me and I'll email it to you.

I get a diagnostic code SPN 1076 FMI 13, which means ECU detects high resistance in the pump solenoid. That code itself causes a 50% of full power derate which is code SPN 1569 FMI 31. Those 2 are the only codes I get which the latter 1569 code is just because of the 1076 code. If by loss of power you mean engine power, You can definitely feel the loss of engine power due to the 50% cutback, but the engine has never shut off completely if that's what you mean. A few times the ecm has cleared the code it's self and everything resumed as normal for 10 to 20 minutes. A couple times it cleared it's self for less than 30-45 seconds and returned.

I have a Deere 4045 manual, but I would like to see what you sent as well. PM incoming.

Thanks all!

 

[Jeff F]

Done. Based on this I'd check everything else very carefully. Sounds like the ECM is doing what it's supposed to do...

You said you changed the pump yourself. Are you confident in its condition and match to the ECM?

 

[Komatsuvarna]

Done. Based on this I'd check everything else very carefully. Sounds like the ECM is doing what it's supposed to do...

You said you changed the pump yourself. Are you confident in its condition and match to the ECM?

Most of the time it is...im still going to play with it some but a few of the glitches makes me lean towards ecu rather than the pump. Im confident in the installation of the pump 110%. I bought it from a Deere dealer right out of a vaccum sealed package in a never opened box. It should be a match, exact same pump visually and ordered it right off the serial tag of the original pump. It worked perfect for 13 hours, right up until it didn't. I'll mess with it some more in a few days.

 

[Jeff F]

Gotcha. I followed the same steps and had failure again at about 40 hrs. Different set of symptoms but all good ever since replacing the ECM.

 

[Nick F]

I get a diagnostic code SPN 1076 FMI 13, which means ECU detects high resistance in the pump solenoid. That code itself causes a 50% of full power derate which is code SPN 1569 FMI 31. Those 2 are the only codes I get which the latter 1569 code is just because of the 1076 code. If by loss of power you mean engine power, You can definitely feel the loss of engine power due to the 50% cutback, but the engine has never shut off completely if that's what you mean. A few times the ecm has cleared the code it's self and everything resumed as normal for 10 to 20 minutes. A couple times it cleared it's self for less than 30-45 seconds and returned.

I have a Deere 4045 manual, but I would like to see what you sent as well. PM incoming.

Thanks all!

I'll comment, as I educated myself extensively on this particular motor over 6 months as I tried to diagnose increasingly alarming symptoms...

You're not missing anything. But I think a solution that doesn't involve a functioning ECM isn't feasible. More modern motors do have 'limp home' modes, but AFAIK if the ECM powers down those features are lost.

If you read through Ted's issue, it wasn't the fault code that triggered the shutdown, it was the ECM powering down. That was my problem as well, and based on Komatsuvarna losing instrumentation it sounds very much the same.

In this motor the ECM controls both timing and duration of the pump. There isn't any way of manually controlling the pump.

Thanks Jeff for this extra info,
I am guessing now that the ECM actually controls the amount of "advance" and the "stroke" of the pump (this latter to vary the quantity of fuel injected). There must be electromechanical actuators to execute this, but they are probably buried inside the pump assembly, making a purely manual (mechanical) override very difficult to achieve.

The adjustment of advance could be fixed at a single setting, sacrificing performance and emissions slightly (many older direct injection diesels have no automatic advance at all). But that still leaves the stroke control.

Has anyone put an oscilloscope on the signal? (ECM to pump) As stated above, it may not be a simple 0 - 5 volts, but a pulse code (pulse width? Pulse frequency? Hi-lo ratio?).

 

[PierreR]

Would be hard to do. Its not "hot" all the time...it basically fires in milliseconds from the ecu to control the fuel supply...although it may appear to have a low voltage on it all the time.

I would think you could mimic it with a pulse generator to run on an emergency basis

 

[Jeff F]

Lots of details here

 

[Jeff F]

Keep in mind that this was a relatively short-lived injection system, when they were working towards better efficiency and emissions prior to going to common rail. I'm not sure Standyne worked with anyone other than Deere on this, and it was only used in one generation of engines.

 

[Nick F]

Lots of details here

Thanks Jeff - I now see how it works and agree that no simple intervention would be possible. The ECM sends a signal which opens and closes a solenoid in the pump in synchronisation with each power stroke - so it is not case of a simple "stroke" adjusting analog signal.

So it appears that a whole, pre-programmed, spare ECM would be the only backup option.

 

[dannc]

...
So it appears that a whole, pre-programmed, spare ECM would be the only backup option.

Which in the past, John Deere would not do, which was/is reprehensible. I THINK I read that JD now allows one to have a spare ECM but they are making it difficult, in spite of agreements, to have owners fix their own equipment.

 

[Komatsuvarna]

This issue was really consistent the last few mornings. Within 30 seconds of cranking it would throw the code as it did before the new pump was installed. With 13 hours of trouble free use from the new pump I was almost convinced the new pump was bad, but the one time gauge issue had me hesitant. I visited my local Deere people and one of their shop mechanics. They weren't very convinced the pump was bad, but also said the ecm rarely fails...even though they had 2 on the shelf. I said well the Deere manual says to change the pump first and then the ecm if it occurs again. They said thats what they would do. So I bought an ecm before I left. The road service guy showed up today. He was hesitant that it was the ecm and suspected the wires. He hooked his computer up and looked at everything and didn't think it looked bad. I said go ahead with the new ecm. He flashed the new ecm, installed it and it appears to be fixed. I dont remember the correct term, but the diagnostic program shows 2 values for the solenoid resistance (decay time) . One is the opening of the solenoid and the other is the closing. Naturally the opening will be higher than the closing. The opening didn't change very much but the closing did change about 40%. FWIW, the road mechanic said he has seen the wiring fail more than a few times and cause the same issue...also he mentioned changing the ends if it occurred again and running a heavier wire. His first bet was on the wiring. My theory is the new pump lowered the resistance just enough to get the failing ecm back inside the trouble free threshold for the 13 hours, until it got weaker. Sorry for the long unorganized post but hopefully someone will find it helpful in the future, just as I did this thread!

 

[Jeff F]

Hope it's all behind you. Please come back if this didn't fully solve the problem.