We recently helped a customer solve his E15 angel indication error on his PAT DS350 Modular on a Grove TMS700B.  Here is a copy of the email:

 PAT DS 350 Modular

Good Evening Customer,
Please refer to attached DS 350 Modular Service Manual. I found sections in the service manual that are suitable and will assist you to follow the troubleshooting procedure to identify the E15 angle problem. For your convenience I have attached the complete manual, in case you may want to check other possible causes, such as pressure transducer problem or you need to refer to drawings.

As you told me that you have the error message E15, you should concentrate on the angle sensor signal troubleshooting. E15 indicates that the angle sensor signal is out of the allowable range. Please refer to below to the E15 troubleshooting information of the DS 350 Modular on your TMS700B. 
·        Troubleshooting flow chart for angle problems, such as E15. Section 3.8 on page 24 of the paper version of the manual.
·        Section 4.10 page 45 of the manual paper version for the analog input module of the central unit. Refer to test points and ensure the voltages and (electrical current) amperages are good.
·        Section 6.4 page 55 of the manual paper version for the theory of angle sensor signal receiving at the analog input board.
·        Please note that electrical current measurements has to be done in series, so the signal wire need to be disconnected and the probes of the amp meter need to be connected in series; one end to the terminal and one end to the removed wire from the terminal, such as in the cable reel.
·        The current (amp) measuring result for the angle channel should be 20mA at 0 degree boom angle, 4 mA at 90 degree boom angle that you can only achieve by mechanically removing the angle sensor from its bracket and simulate 90 degree.
·        For assistance, I usually check the value at 45 degree boom angle that should read 12mA in series.
Please let me know if you need further information and I am glad to assist you and your technicians at my earliest convenience.