873 F series

[overworked]

Have a 873 s\n 514125712 bics lift tilt light won't come on , lift tilt won't work. I have service manual butfor wrong serial numbers. Any ideas, thanks.

 

[willie59]

I've never worked on an 873F, but if they're similar to other F series models, I assume it has the BICS control box on the right side of seat on back wall? If so, do the other 3 LED lights light up? Just the lift/tilt LED not working? Does the lift/tilt LED make any flashes?

 

[overworked]

Hello Willie yes it has bics when you turn key on all lights on controler come on then go out, then power light on, drop seat bar and that lights, release traction lock and push to operate and that lights up. Lift and tilt light won't come back on. I don't understand what system is looking for to unlock. I have 3.25 volts at bics solenoid. Thank you for your thoughts.

 

[overworked]

No flashes, i unplugged the solenoid to see if it would bring up a flash code but still nothing.

 

[willie59]

It's been a long time since I've worked on a F series Bobkitty so my comments are as dated as my age, and that I have no experience with the 873F only makes that even more unsure . The BICS system on the F were very early stuff, much like OBD-I on automotive systems, able to do self diagnostics at a very rudimentary level. In that all other LED's light, seat, seat bar, traction, and power, remain lit, to a certain extent, that indicates the BICS controller is operating proper. It at least indicates the problem is either a faulty BICS controller, or most likely, a problem with the lift/tilt lock solenoid circuit.

If the lift/tilt solenoid is shorted out, the BICS controller will typically sense that and give a flash code on the LED. Likewise, if it has a open circuit to the solenoid, it will sense that as well giving a different code. That's what's curious in your case, if you disconnected the harness to the BICS solenoid at the control valve it should have given you a flash code, kind of indicates a problem with BICS controller. But 3 something volts at BICS solenoid is also curious, should be more volts than that for certain. Possible causes: 1) shorted solenoid (but that should flash a code, 2) faulty BICS controller, or 3) bad wiring or bad connections at wiring connectors.

Again, it's been a long time since I've worked on a F, I can't offer specific advice, only hope my advice gives you something to think about in solving your problem.

 

[overworked]

Willie , can you remember what voltage bics uses to lockout solenoid. books say less than 12 volts but it don't say what. Service manuals king of vague.

 

[overworked]

This is a late serial number, with no seat switch.

 

[willie59]

My problem is I have no info for the 873F, and it's been years since I've kicked the tires on any F model. If I recall, a number of BICS solenoid coils work on somewhere around 9 volt, if you use 12V to test them it will damage them, but I'm not entirely certain about that voltage. However, I've never seen any solenoid coil work on 3.25 volts, that would surprise me if that were correct. I still think you have either a faulty wire, a faulty connection, or a faulty BICS controller, there's just no way I can know which though given the lack of info I have on this machine.

 

[overworked]

I understand, when i get the update for my crystal ball i will be shure to pass everyone along a copy for theirs. . I will post the final result when we reach it, Thanks

 

[overworked]

Willie, still working on this in spare time, i believe my problem is with the AHC , there are two leds on left control and thy don't light up. i guss i will have to buy a book for correct serial number, the one i have is to low, thanks.

 

[willie59]

Ahh, now you add that important little piece of info...Advanced Hand Controls. That's a completely different animal. I've not even had the pleasure of working on one of those units. However, I've stumbled across the PDF manual for 873, and from what little I've absorbed from it thus far, if you have a fault with AHC controllers, wiring, or actuators, you would be seeing flash codes at the LED lights on left control lever. I haven't found anything that specifically describes your situation, but you said upon ignition power up, all BICS LED's come on then go off (probably a self test), then power LED stays on, drop bar and that LED comes on, push the traction lock button and that LED comes on, but you never get the LED for lift/tilt. The only thing the BICS troubleshooting says about that is "AHC has detected a diagnostic condition OR Hand Controls not in neutral when engine was started". And since you have no flash codes at the control handle LED lights, such as 1 flash indicating controller not in neutral on start up, that kind of indicates you have a problem with the AHC module.

Additionally, according to what I see in the manual, when you turn on ignition switch and power up the AHC module, the left LED should light up for 1/2 second, then the right LED should light up for 1/2 second to indicate LED lamps are operational. If you're not even seeing that then you may have a problem with AHC module or AHC module is not getting power input.

 

[overworked]

Thanks Willie, i have power and ground into ahc module, i will check LED bulbs today, had to take a break from it, headache was getting pretty bad. HaHaHaHaHaHa, does you manual have instuctions to flash codes from module with the leds on control handle?. Overworked.

 

[willie59]

Not sure, but there is a section at the end of the manual that has a bunch of info about AHC controls.

 

[overworked]

Willie, I got a pdf version of correct manual yesterday, going through voltage tests today , will keep ya posted, Overworked