Testing angle sensors on Z80

[92U 3406]

So I've got an issue with a Genie Z80/60 (s/n starts with Z8015). I'm suspecting the primary boom angle sensor is shot as it reads 40 degrees on the LCD panel regardless of boom position. Just wondering how one would go about testing the sensor to make sure its not a wiring issue. The angle sensor appears to be located at the rear of the boom and is a small, sealed black box with an adjustment link attached to it.

 

[Johndoe]

first try to calibrate the angle sensor per the Service manual (p/n 1268556 pag 51) link : http://manuals.gogenielift.com/Parts And Service Manuals/data/Service/Z Booms/1268556.pdf
- you can not test the internals of the primary boom angle sensor (p/n 88149GT) BUT you can check power and ground! Go to the second to last page of the service manual grid N/O-13
- test and inspect the J20 18/19 harness running up the the angle sensor
-Grounds: Pin 3,7,11 all tie into the lower control box "P2" connector pin 25 (P2-25)with the harness disconnected from the angle sensor. Ohms out each wire to P2-25. should be =/< 1.0Ω on each wire.
-Power: plug everything back in. power on the unit and the key to service bypass (you should now have power on your P11 circuit) Using BATTERY negative for your ground (Not the other pins in the plug or the chassis) check for 12v on pin 8 at the angle sensor
-If the harness checks out and you have good power / ground to the sensor and the unit will not take calibration, than replace the sensor (p/n 88149GT)

 

[92U 3406]

Thanks for your response! I was actually trying to find this thread the other day to post my findings.

Turns out I was not aware that the display on the ground control panel does not display anything below a 40 degree angle. It will just display <40 (I had originally thought the "<" was the symbol for angle, not "less than"). I used a digital level to confirm that the machine was getting the proper signal from the PBAS once I discovered that.

My original issue was that when lowering the tower boom from fully elevated to the stowed position, the primary boom would lower rapidly and actually lock out the boom functions because it would come down to the ground before the tower was even half way down. After seeing the the PBAS reading on the display appearing to be stuck at 40 degrees I thought maybe this was the result of the machine getting a false reading from the PBAS. I ran a cycle time check on the boom and found primary boom down function was 25 seconds faster than spec. I adjusted it down to the higher end of the spec and it works perfectly now.