Marshall jvm215 no red and yellow modes on overdrive channel

[tommyh]

Hello, I bought this unit new 2 years ago. I have used it rarely,perhaps 100hours. I recently discovered the yellow an red modes in the overdrive channel do not work. The lights work and you can hear the amp pushing more power,however no guitar sound can be heard,I checked to see if all tubes are lit,and they all are( if that means anything) all other modes work ; thanks in advance

[Pedro Vecino]

I think yellow and red modes are assigned to a 12AX7 extra in relation to green mode in ch2. Try a new tube an replace each of the originals ( one at a time and then try). Although a tube lights may not be working.

[tommyh]

I think yellow and red modes are assigned to a 12AX7 extra in relation to green mode in ch2. Try a new tube an replace each of the originals ( one at a time and then try). Although a tube lights may not be working.

ok thank you

[tommyh]

I think yellow and red modes are assigned to a 12AX7 extra in relation to green mode in ch2. Try a new tube an replace each of the originals ( one at a time and then try). Although a tube lights may not be working.

i replaced the tube with the metal jacket (cover) 12AX7 now it works fine, thanks again