Cat 312B no high speed travel

[CatKC]

I have a 312B that won't go int RABBIT travel speed.
Checking things in SERVICE MODE it -will- travel fast when I set 16-13 (travel pressure switch). There are no error codes.
However, the STATUS OF TRAVEL SPEED SWITCH (10) always shows - "1" LOW - even when the CONSOLE shows RABBIT. (engine running or not)
The travel has been working and switching back/forth, but just quit.

 

[CatKC]

Does anyone know if the STATUS OF TRAVEL SPEED SWITCH in SERVICE MODE should indicate "1" LOW when the console has RABBIT lit up ?
If not, does anyone know what would cause this ?

 

[DEMLONE70]

Status of the switch need to go HIGH in SERVICE MODE

 

[CatKC]

Status of the switch need to go HIGH in SERVICE MODE

Do you have any suggestions as to what might cause it to be in LOW while the console shows HIGH (RABBIT) ?

 

[DEMLONE70]

Do u have serial number ?

 

[CatKC]

do u have serial number ?

312b
sn= 9gr00432k

 

[DEMLONE70]

Its the AEC switch on the main valve .U have 2 of them one for travel and one for implemt Part nr . is 1060179 . U can put a wire between the 2 end of the harness to see if its change in the monitor from low to high .

 

[CatKC]

Its the AEC switch on the main valve .U have 2 of them one for travel and one for implemt Part nr . is 1060179 . U can put a wire between the 2 end of the harness to see if its change in the monitor from low to high .

Thank you for the suggestion-
I jumpered both but it still shows "1" LOW when running or not running the engine with the console showing RABBIT.
I also continuity checked the sensors. One goes off/on when trying impements, the other goes on/off when traveling tried.

 

[DEMLONE70]

Speed shows on monitor normally
Do u have logged fault codes ?
Does AEC working ?
Can u read pump pressure in monitor ?

 

[CatKC]

Speed shows on monitor normally
Do u have logged fault codes ?
Does AEC working ?
Can u read pump pressure in monitor ?

No logged errors.
AEC works correctly
I started off by checking the pump on the monitor which was 40000 kPa (5802 PSI)

What's confusing me is that 'I thought' the Service Mode indicator on the monitor should read HIGH if it was in RABBIT MODE even if the engine was not running, which it doesn't.
I realize that any 'perceived' load will drop it into LOW but with the engine off there should be no 'load'.

 

[DEMLONE70]

How do u know pump is ok ? Pump pressure switch makes the travel mode change from low to high turtle or rabbit
Service mode indicator 16-13 shows on or off from travel pressure switch
Engine needs to run to do the test with safety bar forward and push the travel pedals

 

[CatKC]

How do u know pump is ok ? Pump pressure switch makes the travel mode change from low to high turtle or rabbit
Service mode indicator 16-13 shows on or off from travel pressure switch
Engine needs to run to do the test with safety bar forward and push the travel pedals

I tested the indicator- (16-13)
It is OFF unless I travel, then it is ON.

 

[DEMLONE70]

Then switch is working now u need to check pump pressure switcht under 21

 

[CatKC]

The 21 pressure indicated was 4000 (x10) kPa

 

[DEMLONE70]

Pressure when u travel or without any mouvement ?

 

[CatKC]

The same both still and moving (slowly).

I'm still wondering abut the 'Status of Travel Speed Switch'. Shouldn't it indicate FAST if the console was indicating RABBIT even if the engine is not running ?
I thought it should reflect the CONSOLE setting.

 

[DEMLONE70]

4000 KPA is standby perssure of pump ,if u want to know the travel pressure u need to block the tracks then u will see pump pressure of tracks , u can hold bucket closed and read full pump pressure
Where do u see the Status of travel speed switch ? Monitor shows rabbit or turtle
What console u talk about ?

 

[CatKC]

4000 KPA is standby perssure of pump ,if u want to know the travel pressure u need to block the tracks then u will see pump pressure of tracks , u can hold bucket closed and read full pump pressure
Where do u see the Status of travel speed switch ? Monitor shows rabbit or turtle
What console u talk about ?

The 312B OPERATORS CONSOLE

 

[DEMLONE70]

Thats called the monitor The travel button shows rabbit or turtel
Does the tracks always stays in slow mode when u travel ?
Travel Speed Control Switch - Press the travel speed control switch in order to select high travel speed or low travel speed. When the engine start switch is on, the travel speed control switch is always set at the LOW SPEED position. Whenever the travel speed control switch is pressed, the travel speed changes.

 

[CatKC]

Sorry, I have seen it referred to the SERVICE CONSOLE as well as the OPERATORS MONITOR.
The CONSOLE/MONITOR/INDICATOR shows RABBIT-sitting or traveling-. It never travels FAST. The SERVICE MODE on the CONSOLE/MONITOR always says (1) LOW -sitting or traveling- with the engine -running or off-. It will run FAST if tested/forced in SERVICE MODE. (see first post) Every sensor/switch I have checked has been working. I have checked pressures and none seems abnormal.

The concern I have is if the MONITOR in SERVICE MODE indicates (1) LOW with RABBIT displayed on the CONSOLE. SHOULD THIS INDICATE (2) HIGH even when the engine is off if the RABBIT MODE is selected ?
To me this would indicate it would not go into RABBIT because it doesn't think it has been selected.