Brake switch
|  | Foot brake pedal terminal connection diagrams
|  | 3-stage foot brake pedal test steps
|  | Continuously variable foot brake pedal test steps
|  | 3-stage hand brake lever terminal connection diagram
|  | 3-stage hand brake lever test steps
|  | Notice: variable signal
Foot brake pedal terminal connection diagrams up to 18.22. (pedal position proportional to voltage) => above 18.22. no zero-load switch (brake pressure proportional to voltage) 3-stage foot brake pedal test steps Open plug connection S2. Depending on what fault is displayed by the diagnosis, shift brake stage according to the following table and measure resistance between contacts. If all measurements yield R = RTarget, continue with point 3.
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | 40 (FB1) | ∞
1 | 40 (FB1) | 0
2 | 40 (FB1) | 0
3 | 40 (FB1) | 0
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | 11 (FB2) | ∞
1 | 11 (FB2) | ∞
2 | 11 (FB2) | 0
3 | 11 (FB2) | 0
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | FB3 | ∞
1 | FB3 | ∞
2 | FB3 | ∞
3 | FB3 | 0
Open S3. Depending on what fault is displayed by the diagnosis, shift brake stage according to the following table and measure resistance between contacts.
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | 1 (FB1) | ∞
1 | 1 (FB1) | 0
2 | 1 (FB1) | 0
3 | 1 (FB1) | 0
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | 4 (FB2) | ∞
1 | 4 (FB2) | ∞
2 | 4 (FB2) | 0
3 | 4 (FB2) | 0
Brake stage | Measurement between +FB and: | RTarget [Ω]
0 | FB3 | ∞
1 | FB3 | ∞
2 | FB3 | ∞
3 | FB3 | 0
S2: Check resistance of +FB, 11(FB2), 40(FB1) and FB3 to vehicle ground. RTarget = ∞ Ω. S3: Check resistance of +FB, 1(FB1), 4(FB2) and FB3 to ground. RTarget = ∞ Ω. The signal +FB must continuously supply 24V. Continuously variable foot brake pedal test steps Check the voltage values while appying the pedal using menu "D" of DIWAgnosis. Open S2 plug connection and check the lines 2 (+FB+HB), 21 (GND) and 49 (VSBG3) for continuity. For a pedal with no-load switch, check also line 40 (VSBG1). If the voltage signal in DIWAgnosis was correct and all lines are intact, please contact the vehicle manufacturer and have the brake pedal tested or replaced. 3-stage hand brake lever terminal connection diagram 3-stage hand brake lever test steps If the pilot light is defective, replace light bulb. Open plug connection S2. Depending on what fault is displayed by the diagnosis, shift brake stage according to the following table and measure resistance between contacts. If all measurements yield R = RTarget, continue with point 4.
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 7 (HBA) | ∞
1 | 7 (HBA) | 0
2 | 7 (HBA) | 0
3 | 7 (HBA) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 26 (HBB) | ∞
1 | 26 (HBB) | ∞
2 | 26 (HBB) | 0
3 | 26 (HBB) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 44 (HBC) | ∞
1 | 44 (HBC) | ∞
2 | 44 (HBC) | ∞
3 | 44 (HBC) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 21 (-UB) | ∞
1 | 21 (-UB) | approx. 290
2 | 21 (-UB) | approx. 290
3 | 21 (-UB) | approx. 290
Open S8. Depending on what fault is displayed by the diagnosis, shift brake stage according to the following table and measure resistance between contacts.
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 3 (HBA) | ∞
1 | 3 (HBA) | 0
2 | 3 (HBA) | 0
3 | 3 (HBA) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 4 (HBB) | ∞
1 | 4 (HBB) | ∞
2 | 4 (HBB) | 0
3 | 4 (HBB) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | 5 (HBC) | ∞
1 | 5 (HBC) | ∞
2 | 5 (HBC) | ∞
3 | 5 (HBC) | 0
Brake stage | Measurement between +HB and: | RTarget [Ω]
0 | Y | ∞
1 | Y | approx. 290
2 | Y | approx. 290
3 | Y | approx. 290
S2: Check resistance of 7(HBA), +HB, 21(-UB), 26(HBB) and 44(HBC) to vehicle ground. RTarget = ∞ Ω. The signal +HB must continuously supply 24V. Notice: variable signal The assignment to a connection of the transmission control unit is accomplished in the data record and is vehicle-specific.
© by Voith Turbo GmbH & Co. KG send remarks to markus.zwickel@voith.com (documentation department)