Manual operation of the automatic transmission on Scania TGB30/40

[SBAT111 1,231]

Since I have been asked abuot this a few times and understand that it may be difficult for non-Swedish speaking people to follow the discussions in our forum I thought I would try a simple summation of the matter.

The automatic transmission for Scania TGB30 / 40 is relatively easy to operate manually (with electric voltage). The easiest way is to locate the electrical connection piece to the right in the fuse panel located at the dashboard (see picture).

This connectionpiece contains all the cables required for control of the gearbox(cables number 18, 18A, 503, 521, 522, 523 and cable number 526).
Connect power to the cables for the gearbox according to the schedule at the top right of this wiring diagram.

You can obtain the connectionpiece from ELFA (https://www.elfa.se/elfa3~se_sv/StartPage.do?ignorecookie=true) part no.44-221-04 https://www.elfa.se/elfa3~se_sv/elfa/init.do?sq=44-221-04&cat=0 and the contaktpins part no.44-221-13 (https://www.elfa.se/elfa3~se_sv/elfa/init.do?sq=44-221-13&cat=0)

[bandar 3]

dear friend can i get your phone number i have question about gear transmission for speed or to send me sms on +974-33339696

[SBAT111 1,231]

I think it would be best if you stated your question here on this page, mabye illustrated with pictures since there are a lot of people with wast experience of the gearbox on this forum.

[SBA111 420]

bandar, replying to your PM question about why the gerbox does not change to higher than H3.

 

First thing,

check that the brake light is not always on,

check that the trailer brake lever under the left part of the steering wheel is fully up/forward.

[bandar 3]

SBA111 thank you . May I have in contact with you to clear this issues regarding the gear transmission .

 

My Mobil no . +974-33339696

[bandar 3]

Or what,s up

[bandar 3]

Or what,s up

[kristaga 939]

974 is the country code for Qatar. Since it might be very expensive to call Qatar I advise you (as SBAT111 also says) to state your questions here at the forum.

[bandar 3]

I will call just mised call & I will call .it is difficult to explan in writing

[bandar 3]

When I drive the truck it change up to three speed with 40km . I could not go for more speed or change the gear to more . What should I do

[bandar 3]

dear freinds 

 

how can i reach maximum speed of scania sbat 6x6

[Wingflyer 3,191]

It sounds like your transfer box might be stuck in low gear (T).

[bandar 3]

how can i know . and to solve it 

[bandar 3]

is there any switch to be pressed 

[SBAT111 1,231]

The rear switch that is marked V and T should be in position V (road)! Also check that the indication light for frontweeldrive (framhjulsdrift) is turned of.

With the engine turned off you should be able to hear the sound of the magnetic valve when changeing from V to T and back. The controlbox just sends a momentary puls on lead 527 to engage V and 528 to engage T.

[bsvensso 705]

Sounds like the throttle pedal switch may be blocking the V-T signals?

[bandar 3]

thank you all . I will check & let you know .

[bandar 3]

i have checked all of the above but still same problem the gear changing upto three with 60 km . it canot move more . do you think the problem from the auto transmision controll unit which undernith the  gear swithch ( aluminum box ) ?

[Wingflyer 3,191]

If you know a little about electrical circuits, etc., you may try with a manual switch between +24V and wire number 524 in the connector block in the picture above.

 

When driving the truck in 60 kmh, flipp the switch so you get 24V on 524. The gearbox should then change to 4'th gear (M3). If it does, your problem is in the control unit. If not, the fault is in the gearbox or the electrical harness...

[Halfsafe 282]

Make sure you have not mixed up the relays in the relay box.

There are 2 different types that look the same but have different function.

Make sure they work and are in their correct position.

[bandar 3]

thank you all.  what do you mean by flipp the switch and which switch ?

[Halfsafe 282]

Here are the positions of the relays:

 

 

Make sure A and B relays are not mixed up.

If I remember correctly they look like this:

 

[bandar 3]

i will check & come back soon 

[Wingflyer 3,191]

thank you all.  what do you mean by flipp the switch and which switch ?

 

This is why I asked if you are familiar whit electric schematics and circuits. You can insatall an extra switch as described, and thus manually test the gearbox fouth gear...

[tbw 2]

Hello all.

 

We have a problem, we bought such military truck from the army and the truck was working flawlessly until now.

We have sold the truck, and today morning the customer has driven the truck to another place and left it there.

 

In the afternoon the guys from that place wanted to move the truck but it is not moving when switched to D.

The terrain and street switch is on V.

 

Before when you put it into drive you could feel that the truck started to move a bit, now nothing happens.

Please help.

 

Could this be an electrical problem.

 

We have checked automatic transmission oil, while the engine was running and the level is good.

 

I tried to lift the back axels, because I thought that the truck is stuck between street and off road gears, but it is not.

Need your help.

 

I doubt that the gearbox went bad on an empty truck, because it was working in the morning, and in the afternoon it does not do anything.

Thanks.