Nige
Senior Member
Actually both of them. They are referred to as A! (#3) and A2 (#2). One sends the oil flow in the AUX in one direction, the other one sends it in the opposite direction. That's what gives you a bi-directional AUX function.
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Cat 247b auxilary hydraulics stopped working
- Thread starter Brenda l Stedman
- Start date
adn3744
Member
makes sense, one last question. fuse box is missing cover/label. do you have a pic of it?
Nige
Senior Member
See attached.
polarisrcr7
Member
I have 2.7v on 997 would this be a sign of a bad computer?
Nige
Senior Member
Can you post a Serial Number please.
What is the problem that you have.?
Unplug the 12-pin connector under the joystick and measure the voltage between wire 994 Blue which is power and 997 Brown which is ground.
polarisrcr7
Member
The joystick all tests good
polarisrcr7
Member
I have no auxiliary hydraulics
Nige
Senior Member
polarisrcr7
Member
PDT01686
Nige
Senior Member
Thank you. So please can you do the tests below and post the results.
1. With the key switch OFF locate the 12-pin electrical connector directly underneath the RH joystick and unplug it.
2. Turn the key ON. Test the voltage on the machine harness side of the connector, marked R-C5, between Pins 1 & 2 (wires 994 BU and 997 BR). It should be 8.0 +/- 0.5v. Tiurn the key OFF.
3. Re-connect the 12-pin connector.
4. Turn the key ON. By back probing measure the output voltage between Pins 2 & 3 (wires 997 BR and 998 GN) with the thumbwheel switch in the centre postion.
5. Roll the thumbwheel all the way in one direction and measure the output voltage.
6. Roll the thumbwheel all the way in the other direction and measure the output voltage.
Post the results from Steps 2, 4, 5, and 6.
polarisrcr7
Member
On the left joystick the top switch is the horn and I found a broken wire for the bottom switch you think this could be my problem? I need to get a replacement pin for the connector
Nige
Senior Member
If you can post some photos of the area around the broken wire I can try to come up with some ideas.
TBH I don’t think that a problem on the LH joystick could cause AUX issues but either way it needs to be fixed.
polarisrcr7
Member
2 I have 8v. 4 I have 2.8v.5 I have 1.1v. 6 have 4.4v
Nige
Senior Member
From the voltage readings you obtained it appears as though your thumbwheel roller switch is working just fine.
Next step is to get under the floor to the Interlock ECM, marked "B" on the illustration below.
You need to backprobe wires P997-BR and P996-GN. You will find them on Pins 52 and 53 of the ECM connector. Then repeat Steps 4, 5, and 6 with the thumbwheel. You should get the same voltage readings as above but we need to confirm.
polarisrcr7
Member
Same readings
Nige
Senior Member
OK, so that means the correct signals are reaching the AUX Hydraulic ECM from the thumbwheel switch.
Now to look at the output voltages to the AUX solenoids A1 & A2.
With the key OFF, unplug the 70-pin connector A-C5 from the AUX ECM. Locate the following wires: -
P978-GN (A1 solenoid power) on Pin 40.
L998-OR (common solenoid return) on Pin 42.
P979-YL (A2 solenoid power) on Pin 58.
On the main implement control valve locate the A1 and A2 solenoids using the illustration in Post #21 at the top of this page.
1. Apply 12v between Pin 40 and Pin 42 of the connector. Listen for a click in the AUX A1 solenoid.
2. Apply 12v between Pin 58 and Pin 42 of the connector. Listen for a click in the AUX A2 solenoid.
polarisrcr7
Member
So at the solenoids I have one wire that has 12v with the key on and the other wire shoes 3v, the only way the solenoid will click is if I put ground to the wire that has 3v going to the solenoid
Nige
Senior Member
I think you misunderstood. I was asking you to unplug the big connector and apply 12v from the battery to one pin while you connect the second pin to machine frame ground. This tests the solenoid and its wiring external to the AUX Hydraulic ECM. You have to do the test twice, one for each solenoid.
Last edited:
polarisrcr7
Member
Already did that and both solenoids operate as they should
Nige
Senior Member
In that case the bad news is that the AUX Hydraulic ECM is the root cause of your problem. It will require repair or replacement.