CAT 226B Parking Brake Indicator and Armrest Indicator Are Flashing

[AustinC]

Hello, I'm trouble shooting Parking Brake Indicator and Armrest Indicator Are Flashing on my CAT 226B serial number MJH08353. In the attached picture, in purple I highlight what I believe is the detent coil. I have two questions, first, is this the detent coil? It's located under my right hand control when in the operator seat. The second question is regarding the amount of resistance/ohms that this should have. I unplugged it and it's reading 53.1 ohms, is that the right amount of resistance for this part?

I have also attached 3 other docs that I'm referencing while trouble shooting.

In the RENR6419-06 - Electrical Schematic document, on page 8, it shows the Solenoid: Detent Valve should have 9.4 ohms of resistance. I'm just not sure if I'm looking at the right part due to different names like dent coil and detent valve.

Thank you.

 

[Nige]

In the attached picture, in purple I highlight what I believe is the dent coil. I have two questions, first, is this the dent coil? It's located under my right hand control when in the operator seat. The second question is regarding the amount of resistance/ohms that this should have. I unplugged it and it's reading 53.1 ohms, is that the right amount of resistance for this part?

That is the detent coil circled in your photo. No idea where the "dent" comes from.

You should have a 172-0970 coil installed at that location. The coil resistance specification is correct on the schematic, 9.4 ohms @ 25 DegC ambient. So if you measure 53.1 ohms that is not correct. Check the Part Number on the coil would be my first suggestion.

 

[AustinC]

That is the detent coil circled in your photo. No idea where the "dent" comes from.

You should have a 172-0970 coil installed at that location. The coil resistance specification is correct on the schematic, 9.4 ohms @ 25 DegC ambient. So if you measure 53.1 ohms that is not correct. Check the Part Number on the coil would be my first suggestion.

Thanks for the quick reply. The "dent coil" was a spelling error, I updated my previous comment to the correct spelling. I just removed the detent coil to verify the part number but it doesn't have any part number information on it. The wire seems like it's melted in spots like it got hot. I bought this machine used so I'm not sure if this was previously replaced. With no part number listed, I'm wondering if this isn't a CAT factory part or if the detent coil doesn't have a part number on it from the factory. Not sure where to go from here other than buying a new coil from CAT. Do you know if this part should have a part number on it?

 

[Nige]

Do you know if this part should have a part number on it?

I don’t I’m afraid. I think your best option is to buy a replacement. You could search online by Part Number and maybe get a genuine Cat one from eBay or similar, but TBH your only 100% guarantee that you are getting a genuine article is to buy one from a Cat dealer.

 

[AustinC]

Okay thank you, I will see what I can find. Do you think that my current detent coil reading 53.1 ohms could be the reason that my parking brake and armrest indicator are flashing?

 

[Nige]

I wouldn’t have thought so, but anything is possible.

 

[Arny L]

That's the electromagnetic coil for the boom float, I believe.

 

[AustinC]

I just made it home from the Cat dealer and now I'm more confused. They had the detent coil part number 172-0970 in stock. The guy at the parts counter was nice enough to let me open and test the resistance on the part with my multimeter and it tested at 54.8 ohms. So what am I doing wrong? The docs say it's supposed to test at 9.4 ohms but I'm getting 54.8 on the new part out of the box. I'm very green on electronics and testing so maybe I'm misunderstanding something. Please help.

 

[Arny L]

Is your meter off. Are you calibrating(zeroing) meter before using, right scale. the long and short is, there is nothing wrong with it.

 

[AustinC]

I'm zeroing and I'm using this setting (see attached pic) on my multimeter. Is this the correct setting to test the detent coil?

 

[Nige]

I’m not sure what that particular setting is. Edit: I found the manual for your DMM. It’s an audible signal for continuity.

I suggest that you turn one click clockwise to the “2K” setting and try again. See if the results change.

 

[AustinC]

Thanks Nige, I just tested at 2k and I'm getting .051

From what I'm reading online, at 2K I would multiply .051 x 1000 = 51 ohms

Am I understating this correctly? If this is correct, the new part at Cat was reading the same or very close to this so I'm confused on where 9.4 ohms is coming from for this part in the RENR6419-06 - Electrical Schematic document

 

[Nige]

I would suggest that you try measuring the resistance using a different meter.

I looked in other places apart from the schematic and everywhere showed the same value for the resistance. Either all those sources are wrong, or your meter is potentially suspect.

 

[AustinC]

I would suggest that you try measuring the resistance using a different meter.

I looked in other places apart from the schematic and everywhere showed the same value for the resistance. Either all those sources are wrong, or your meter is potentially suspect.

I tested again with a cheap Astro AI meter I had laying around and the coil tested at 52.8 ohms so I'm not sure what's going on with the docs referencing 9.4 ohms. To make sure I'm testing the detent coil correctly, I'm simply unplugging it and testing continuity between the two wires on the coil, is that the correct way to test?

 

[AustinC]

I'm looking at the attached doc for trouble shooting the armrest indicator is flashing. On step 17, it's saying the detent coil should be 12 ohms, not 9.4. Is there a newer version of the trouble shooting document or does it seem that there is different information on the resistance for the detent coil?

 

[Arny L]

It says to check the wires of the coil, not the coil itself, if you read it. Did you do all the previous steps in your diagnostics?

 

[AustinC]

Thanks Arny, when you say "check the wires of the coil, not the coil itself", I'm testing the two wires that connect to the coil circled in red in the attached picture. I should not be testing the wires circled in yellow that connects the coil to the harness, is that correct?

At this point based on the results when following the trouble shooting steps in the Parking Brake Indicator and Armrest Indicator Are Flashing (RENR6417-01) and the Armrest Indicator Is Flashing documents it seems like I have an issue with my wiring harness.

With that said, I'm concerned that I'm looking outdated/incorrect documents because the Armrest Indicator Is Flashing doc says the detent coil should be 12 ohms and the RENR6419-06 - Electrical Schematic document says detent coil part number 172-0970 should be 9.4 ohms.

Can anyone clarify why the two documents are calling for different ohms on the detent coil?

 

[Arny L]

Sorry, I misspoke, you’re doing it right, according to manual. But ya, according to manual, anything other than 12 ohms is faulty coil. But you’re getting the same reading on new one, correct? Did you do any of the other testing procedures, I glanced at them, and there are quite a few, for your issue. I wouldn’t sweat the 12 ohm vs 9.5 discrepancy. That circuit you’re testing is for the float, and I’m sure it’s 12v and ground. You can test with key on, and shove joystick forward, it should lock in place. Not sure if your aware of that.

 

[AustinC]

No worries at all. Yes that's correct, I tested a new one out of the package at the Cat dealership and it measured very similar to mine. I'm familiar with how to put the machine in float mode, the only problem is that with the parking brake and armrest indicator flashing I can't get the machine or the bucket to move to test the float. It will start but the controls aren't working.

I will mention that after leaving the battery disconnected then reconnecting, sometimes the machine will work fine but as soon as I lift the armrest and get out of the machine the parking brake and armrest indicator start flashing.

I just went out and disconnected the battery, I will let it sit for a bit and then attempt to start it and see if I can test the float.

 

[Arny L]

I think I asked already, but did you follow the procedure in RENR6417-01.