Volvo Mini Excavator- erc48C Swing Brake will not release except with thumb activation

[volvoerc48c]

This has to be simple but my excavator swing brake will not release with any machine function except for me activating the thumb which is the boom angle as well. I have used a volt meter and I am only getting voltage to the swing brake solenoid which I think is mounted on the back side of the vertical bar when I press the thumb function but then it locks the swing brake after 5 seconds.

Any volvo or swing brake experts have ideas?

 

[Mick-the-fitter]

Remove the two connected wires to the solenoid for the thumb see if swing brake works?

 

[doobin]

Can't help you but its nice to see a bloke who appreciates the benefits of steam cleaning things before you try to work on them!

 

[volvoerc48c]

thank you Mick - the - fitter, I don't have a manual nor wiring diagram so i am not ware where the solenoid is for the thumb? Anyone have a manual or location?

 

[Mick-the-fitter]

Try this one first, pull the wires off, tape them so they don’t touch anything!

 

[V8Druid]

Try this one first, pull the wires off, tape them so they don’t touch anything!

looks like a pressure switch Mick

 

[Mick-the-fitter]

Oh yes well spotted Gra, I went for that as it looks like a bolt on item!!

 

[Mick-the-fitter]

Maybe the one bolted behind, as the hose coming to the right hand 90 looks a bit odd beyond!

 

[CPS]

When you say Slew brake, do you mean as in a switch you flick to brake it? or when you go to slew the slew not releasing?

I could be wrong but I don't think you'll have a solenoid for the slew brake

 

[CPS]

Try this one first, pull the wires off, tape them so they don’t touch anything!

Ok, Had a look in the manual, This is the "Slew brake, pressure sensor"

It takes its signal from that back into the Vehicle ECU

 

[CPS]

When you say Slew brake, do you mean as in a switch you flick to brake it? or when you go to slew the slew not releasing?

I could be wrong but I don't think you'll have a solenoid for the slew brake

I stand corrected i was wrong,

The slew solenoid is mounted behind the bar, MA9402

 

[V8Druid]

When you say Slew brake, do you mean as in a switch you flick to brake it? or when you go to slew the slew not releasing?

I could be wrong but I don't think you'll have a solenoid for the slew brake

'Drema has one - solenoid failed and it was locked solid .. bloody annoying and took some sussing/finding

 

[V8Druid]

Ok, Had a look in the manual, This is the "Slew brake, pressure sensor"

It takes its signal from that back into the Vehicle ECU

could've failed internally then -- again had a very similar looking one fail, but that sh*t itself all over the floor, so was an easy / deffo bollo-ed find