Speed Limiter

Information 

Speed Limiter Requirements for Buses 

This inspection applies to all buses that are required to be fitted with a speed limiter unless they are exempt. 

A vehicle is exempt from needing a speed limiter if the vehicle construction means it cannot exceed 100km/h. If this is the case, the declaration on the application form must be completed. 

Bus/minibus requiring a speed limiter:- 

A. A bus/minibus fitted with a diesel engine and having a design gross weight not exceeding 10 tonnes, first used from 1 October 2001. 

B. A bus/minibus first used on or after 1 January 2005 

Specific Exemptions 

The following buses are exempt from speed limiter fitment if first used from 1 October 2001 to 31 December 2004: 

• Any petrol engine or petrol engine converted to run on LPG

• Citroen Relay 2.0 litre and 2.2 litre HDi engines 

• Fiat Ducato with 2.0 engines (engine code RHV) 

• Ford Transit (all) 

• Isuzu models NPR, NQR and NKR with T, V, W, X or 1 (one) as the 10th VIN character. 

• Iveco Daily all, except vehicles with engine codes F1CE---, 8140.43B, 8140.43N and 8140.43S with PIC code ‘G.’ (the PIC code is applicable to the 8140.43S only, the PIC code can be found on the ID plate on the shut panel for the bonnet identified by the third character.) 

• LDV (all) 

• Mitsubishi Canter with ‘R’ as the 12th VIN character 

• Nissan Interstar all, except vehicles with engine codes ZD3-A202, G9U-A754, S9WA702 & G9U-A724. All Primastar. 

• Peugeot Boxer 2.0 litre and 2.2 litre HDi engines 

• Renault Master all except vehicles with engine codes ZD3-A202, G9U-A754, S9WA702 & G9U-A724. All Trafic 

• Vauxhall/ Opel Movano with E,F,G,J,K,L,M,N,P,T or W as 7th VIN character 

• Vauxhall/ Opel Vivaro (all) 

• Volkswagen (all except 2.5lt/2.8lt 109bhp/158bhp engine codes AVR & AUH respectively.) 

These vehicles have either been fitted with a Euro 2 engine or comply with the engine type approval/emission requirements of EC Directive 70/220. It is possible that other vehicle types first used between the specified dates may be similarly exempt, however customers must produce documentary evidence issued by the manufacturer, before this can be accepted. This documentary evidence should be forwarded to ROM’s. 

Method Of Inspection 

Check that a speed Limiter plate is securely fitted in the driver’s compartment. It is acceptable for the plate to be fitted in a doorjamb. If fitted on a window and facing outward the details must be able to be read by a person of average height standing on the same ground as the vehicle. 

Check that the plate is clearly and indelibly marked with the speed at which the speed Limiter has been set (the speed may be shown in mph or km/h). 

Note:  The character and composition of the plate and size of the lettering are not important provided the details are legible. 

Check the presence and security of the device, the actuating mechanism, wiring and the tamperproof devices such as seals or lock nuts. This inspection is only for the parts that are visible without dismantling. 

Note: It is acceptable for the Limiter to be wired through the "ignition" switch but any other device which would allow disconnection of the speed Limiter whilst driving is unacceptable. 

Speed Limiter Integrity Check Using Electronic Device 

Vehicles without a Tachograph fitted or with a Digital Tachograph fitted 

The functional speed limiter test cannot be carried out on these vehicles. Therefore, examiners are advised to restrict the relevant speed limiter tests to a visual inspection only; customers are not required to produce any supplementary evidence to confirm the vehicle’s restricted speed. 

Vehicles Fitted with Tachographs Other than Digital 

Open tachograph head. If seals need to be removed from within the tachograph head then do so. Plug the speed simulator jack plug into the tachograph head and close the head. 

Seals can only be removed and replaced by approved tachograph sealing centres or DVA staff. 

The machine will establish the pre set K factor. Check that this is within + or – 50 digits of the K factor displayed on the tachograph calibration plaque. 

Select “automatic mode” on the machine, select type of vehicle e.g. > 12000(Goods Vehicle) or Pub > 1/1/88 (Bus or Coach). Start engine and note whether engine can be revved up. If the speed limiter has restricted the engine revs to a noticeable degree the test is complete. Should the engine behaviour not have been noticeably affected by the automatic test a manual test will be necessary as follows; 

Start engine and run at 1200-1500rpm. Input a simulated speed to 80km/h. Check that the tachograph indicates the same speed. Gradually increase the simulated speed in 1 km/h steps. Note the speed indicated on simulators digital display when the speed limiter operates. This can be identified by a reduction in the engine RPM, or a change in the engine note, or vibration indicating that the fuel supply is being reduced. 

On some vehicles the electronic device will be unable to proceed through its set programme (possibly due to no/poor earth connection or because the vehicle senses road speed from another source such as ABS systems). Under these circumstances tachograph chart evidence of the vehicle while in service can be used to verify the operation of the speed limiter. The submission of 5 consecutive tachograph charts from the previous 28 days can be used to establish the maximum operational speed. The vehicle should be failed for Reason 3a if the tachograph chart shows a speed trace of more than 110km/h for Buses. The vehicle must have exceeded this speed for at least ten minutes. 

If the speed simulator is unable to be used, and there are no tachograph charts available for inspection, confirmation of the functionality of the speed limiter from an authorised speed limiter fitment centre issued within the preceding 28 days will be acceptable. 

A simulated response will reflect in service road speed. The vehicle types and speed limiter test applications standards are as follows.

Vehicle Type	Response speed at which vehicle will be failed
Bus	More than107km/h

Reasons For Rejection

		Reasons For Rejection	Deficiency Category
1		Speed Limiter Plate:
	A	Missing.	MAJOR
	B	Insecure	MINOR
	C	Not in a conspicuous position.	MINOR
	D	Not clearly and indelibly marked with the required particulars.	MAJOR
2		Set speed marked on Speed Limiter Plate greater than 100km/h (62.14 mph) for a relevant bus.	MINOR
3		Response speed of more than 107 km/h for a relevant bus.	MAJOR
4		Speed Limiter:
	A	Not fitted or obviously inoperative.	MAJOR
	B	Insecure.	MINOR
	c	Actuating rods/cables disconnected or damaged so that the operation is obviously affected.	MAJOR
	D	Wiring disconnected or can easily be disconnected by unauthorised means.	MAJOR
	E	Tamperproof device missing or defective or showing obvious signs of interference.	MAJOR