Allison B500 Code 45-23, 24-23 | Retarder stuck on, off?

[travelingchuck]

Hello Bus Nuts,

I have a '95 D3 with a retarded Allison B500 and Series 60 engine. 

I'm getting allison codes:

45-23 Open circuit, H solenoid circuit
24-23 Sump oil temperature, hot

These also came with a hot engine code / check engine, which makes sense since they share coolant. 

Looks like the H solenoid is the accumulator, which is related to the retarder. 

Does anyone have any experience with this? 
What exactly is happening when that solenoid is stuck open?
I have the retarder turned off at the dash, but is it stuck on?
Is there a quick fix / limp home option for this? Cutting a wire, shorting a wire, crimping the retarder air line?

Any help is appreciated. 

Many thanks,
Charles

[digesterman]

Is there a breaker in the rear junction box you can pull?


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[luvrbus]

Most all the 45 codes 12 thru 26 are ground or connection problems ,24-23 should clear when the temps are normal,  bad connections or grounds throwing the 45 codes will cause the other codes also 61 is the code for over temp on the retarder clean the connections and grounds you should be good to go

good luck

[TomC]

I just love my mechanical engine and transmission.