Diff lock issue

I am working on a 2009 Volvo vhd tandem dump truck with a d13 engine and Rockwell drives. The problem I am having is when the rear diff lock switch is engaged the indicator light (image of two wheels with a x in center) on the cluster will blink. I have installed a new lock switch that threads into the diff as it was broke. The diff lock does activate. The front diff lock engages and the indicator light (image of 4 wheels with x in center) illuminates solid. The 10 amp fuse that powers the switches is good. The only other thing that I need to repair on Monday is the rear diff electric solenoid block that is mounted to the cross member behind the cab that controls the air to the diff is leaking air in various spots around the air line. So I have a new solenoid assembly to install. I am doubtfull this will solve the problem unless the solenoid connections in the electrical plug is corroded. I should also mention the diff light will also blink randomly even when the diff lock switch is in the unlocked position. Any suggestions as to what could be the problem or what else to check is appreciated.

 

Little disappointed that 109 people viewed and no one had any advice to offer I am still going to update the thread. I belong to another truck forum and asked this same question today and within 5 min I had an answer. I was wrong thinking the one switch was front and the other was rear. The one switch is basically a power divider and the other is rear diff cross lock. It is normal for the cross lock indicator icon to blink as it is acting like a warning so operator does not turn a corner with the cross lock engaged. So basically there is no problem. Just have to check that indicator light is not coming on when switch is out as I thought it might be.