Disconnected plugs under dash

[Obi-Wan-YJ]

I have a 2016 XR4145. This week, I pulled off the kick panels below the dash and noticed that on the right side, there are two matching plugs that are disconnected. What are they for? Should they be reconnected?

On a related note, I heard that there was a diagnostic plug under here somewhere. I was hoping it was OBDII-compatible. Anybody know where I could find that?

 

[Roadworthy]

Try asking the prior owner about the plugs. If everything works they may be for an optional accessory. As far as OBD II is concerned a tractor's connector may fit an automobile's reader but to not expect the codes to mean the same things.

 

[GS650GL]

There is an OBD diagnostic connector but the center panel may have to be removed to get to it. The OBD connector can be unplugged from the harness so that the dealer can hook up their service tool laptop directly to the harness without taking off the center panel to access the connector. It's kind of a shortcut. It appears the connectors in your pictures are of the OBD connector unplugged. The dealer probably used the shortcut and didn't plug it back in, which makes no difference unless you remove the center panel and try to use the OBD port. It could be plugged back in, but an automotive code reader used on the OBD port will not be able to read tractor fault codes because they are different. Codes can be read on the instrument cluster and use a fault code list to see what they mean. I have a list printed out for my use, and someone has a list posted in this forum somewhere but unfortunately, I don't remember where I saw it. Someone else may be able to help with that.

 

[Obi-Wan-YJ]

So do those two plugs definitely belong together? I don't want to short something out by connecting two incompatible plugs.

So the OBD port is behind the lower center kick panel? Pity they didn't put it behind one of the side panels that are easy to remove with thumb screws.

How do you display the codes on the instrument cluster?

@GS650GL any chance you could post a picture of that printed list that you have?

 

[dodge man]

You’d probably need a wiring diagram to figure out the plug ins.

 

[ptsg]

So do those two plugs definitely belong together? I don't want to short something out by connecting two incompatible plugs.

So the OBD port is behind the lower center kick panel? Pity they didn't put it behind one of the side panels that are easy to remove with thumb screws.

How do you display the codes on the instrument cluster?

@GS650GL any chance you could post a picture of that printed list that you have?

Accordingly to the part number and parts catalogue, on of those plugs goes indeed to the diagnostic port, which is the round one and not the OBD2 on the automotive industry.

 

[GS650GL]

I don't know why they put the OBD port behind the center panel. You have to remove a few screws to take the panel off to connect to the port. That's why the dealers have an adapter plug that connects to the harness to make it quicker and easier. They unplug the port and connect directly to the harness by only removing the right dash panel. You don't need to do anything to display the codes on the instrument cluster, they show up when they occur and start flashing. The exclamation mark symbol lights up and there will be an open book symbol on the left side with the letter S and a number. Below that will be the letter F and another number. For example: S636 F02 is for crank signal from the crankshaft position sensor. Most codes go away when the problem is fixed but will still be stored in code history which can only be retrieved by a scanner or the dealer service tool. I saw a scanner for sale online somewhere for these tractors. Automotive scanners may not reliably recognize tractor codes. I will try to post the fault code list later when I have time. It's 5 pages and about 180 engine and emission codes, but does not have the new power clutch transmission codes.

 

[GS650GL]

OK, here is the fault code list as promised. This should make things easier for everyone so you don't have to call the dealer every time to find out what the codes mean. It doesn't tell you how to diagnose it, but it still helps to know what the code means. Like the S97 F2 which means you just need to drain the water out of the fuel filter, so no diagnosis is needed. The dash will display all F numbers as 2 digits, so an F8 on the list will show as F08 on the dash, but it is the same number. S1485 F7 main relay fault can be a little confusing. It is caused by low voltage getting to the instrument cluster from a poor connection or ground, or even a weak battery while trying to start. It does not always mean it is a faulty relay. Remember, fault codes can be misleading at times. They are not 100% accurate. Hand or foot throttle codes are not always caused by the throttle sensors. They share the same 5 volt sensor power supply with the crank sensor which is more likely to fail than the throttle sensors. So a bad crank sensor could mislead you by setting a throttle code. Codes may not show up again after the key is turned off and back on, so write them down or take a picture of them.

 

[Obi-Wan-YJ]

Thanks! That's great info... although I do wish the entire system was more user-friendly like the automotive OBDII system is. I don't currently have any indication of problems, but I wanted to be prepared when one appears.

 

[alexpops]

Tractors are on the forefront of the whole Right to Repair fight. Car companies have tried to make it as difficult as possible, but given the number of car owners vs tractor owners, legislation has allowed access to the proprietary software on cars (provided you fork over cash for the readers/programmers). Tractors don't have the number of voters impacted, so it's more of a problem getting legislative movement (just ask any owner of modern Deere equipment). Tractor companies still maintain that they own the code that controls your tractor & you only have a use license ... any exploration/changes need to be done at a dealer certified by the company using their certified equipment for diagnostics. At present, you can A) buy the readers/programmers used by OEM/Dealers but it's not certain you'll have access to all the software or updates. Alternatively, B) buy a chinese clone of the OEM diagnostic equipment for 1/3 to 1/2 the cost of OEM & rely on their hackers to provide you the controls you need. A) will cost you more, & unlikely to be practical unless you are charging for repairs on others ... B) will save you money, but may not have all the tools you need BUT, may offer multiple vehicles in their database so you can spread the cost across more than just the tractor.

Last time I looked, the code reader/programmer used in the LS manual was around $3K plus annual subscription costs. A bi-directional Launch with a heavy diesel module runs about $1700-2K, but won't re-program, only does testing & remote control of features. You'd need to also invest in an ECU programmer (KESS/KTAG chinese clone) and a PC for a few hundred as well as the appropriate adapters if you actually want to change the OEM values (think hot rodding).

 

[GS650GL]

There is a scanner advertised from lawntractorco.com that is $189.99 and will read codes and it says it will read some live data, but obviously is limited in capabilities for that price. From the description, it sounds like it can't clear the codes or do any tests so I wonder how useful it is. But then again, I was a diesel tractor service tech for 40 years so I'm used to a service tool that was thousands of dollars and we had to have a $1000 per year subscription for each tool in our shops. This was so we had constant updates to ECM software and new features as new models of machines came out. Besides fault codes, we could do all the tests and had access to schematics, diagnostic steps, updating software, programming, calibration, configuration, service bulletins, knowledge database, and we could go online with the equipment manufacturer. But I did buy an ELM327 for $18 to work on my car and truck and was impressed with what it can do for the price. Not like one that costs 3K, but still helpful. Maybe someone that has the $189.99 tractor scanner can share their experience with it and tell us if it's worth it.

 

[CliffordK]

Looking at the plugs. There appear to be 4 matching male and 4 matching female connections, and 4 blanks. Just that pattern alone (along with the proximity of the wires) indicates they probably go together. You can also look at the wires to see if they are color coded, if you can see them.

I'd probably test reconnecting. However, they may have been disconnected for a reason. Perhaps annoying safety sensors? Alarms? Lights? Battery drain? Or even something that was non-functional like a malfunctioning safety sensor.

 

[Obi-Wan-YJ]

There is a scanner advertised from lawntractorco.com that is $189.99 and will read codes and it says it will read some live data, but obviously is limited in capabilities for that price. From the description, it sounds like it can't clear the codes or do any tests so I wonder how useful it is. But then again, I was a diesel tractor service tech for 40 years so I'm used to a service tool that was thousands of dollars and we had to have a $1000 per year subscription for each tool in our shops. This was so we had constant updates to ECM software and new features as new models of machines came out. Besides fault codes, we could do all the tests and had access to schematics, diagnostic steps, updating software, programming, calibration, configuration, service bulletins, knowledge database, and we could go online with the equipment manufacturer. But I did buy an ELM327 for $18 to work on my car and truck and was impressed with what it can do for the price. Not like one that costs 3K, but still helpful. Maybe someone that has the $189.99 tractor scanner can share their experience with it and tell us if it's worth it.

This thread from last year has a guy talking about using that scanner. His experience was positive.

https://www.tractorbynet.com/forums/threads/ls-scan-tool-available.452383/

 

[RayIN]

John Deere lost the court battle for right to repair in 2023.

 

[RayIN]

Accordingly to the part number and parts catalogue, on of those plugs goes indeed to the diagnostic port, which is the round one and not the OBD2 on the automotive industry.

It is a Deutsch connector for HD vehicles and industrial equipment.
Cummins Engine uses that 9-pin J1939 ECM connecter for everything above the 6.9 engine.
There is a newer design out that has 11 pins.

 

[m5guy]

I'm going to guess they are plugs for options your doesn't have. Like if your tractor is hydro drive, those plugs might have went to the control for the power reverser and adjoining idiot lights on the dash. When you turn your key on all the lights light up. Some of the lights you never see because of how your tractor is equipped. I'm sure ls only uses 1 harness and then plugs in what needs to for equipment on the tractor

 

[GS650GL]

This thread from last year has a guy talking about using that scanner. His experience was positive.

https://www.tractorbynet.com/forums/threads/ls-scan-tool-available.452383/

Yup that's the one I was thinking about. I knew I saw it in this forum somewhere. Thanks for finding it.