Motive's Remote Tachograph Download (RTD) solution lets you download driver card and vehicle unit files remotely, without visiting each vehicle with a download key.
Overview
This guide explains how to physically install the AI Dashcam Plus for RTD on vehicles of 2.5 tonnes and above fitted with a digital tachograph. The step-by-step technical instructions covers an installer needs, including how to choose the correct connection path, how to wire the tachograph's rear C port, and how to verify CAN bus termination so remote downloads work reliably. This guide covers the hardware installation only. Feature enablement and company card setup in the Motive Fleet Dashboard, as well as Motive's remote card hosting service, are covered in separate Motive Help Center article.
Tools required
- Screwdriver set
- Plastic pry bar
- Cutting pliers
- Gripping pliers
- Tachograph removal pins
- Socket set
- Multimeter
- Spare wires
Supported tachographs
VDO and Stoneridge digital tachographs, generations 1.0, 2.0, and 2.2. Some VDO and Stoneridge units require a one-time activation at an authorised tachograph workshop before remote download will work.
Cables and Accessories
| # | Name | Mandatory / optional | Image |
| 1 | VCBL-Y-FMST-R02 | Mandatory | |
| 2 | Tacho C Y-splitter | Mandatory | |
| 3 | Tacho C 120 Ω resistor | Optional |
|
| 4 | CAN Sniffer Harness | Optional | |
| 5 | C7-C8 loop wire & pins | Optional (Not provided) |
|
Choosing the Installation Scenario
Scenarios 1 and 2 (direct Tacho C connection) are the recommended approaches. Use Scenario 3 only if the Tacho C port is sealed or unavailable.
| Scenario | Situation | Connection |
|---|---|---|
| 1 | Both FMS port and Tacho C in the vehicle are active/available | Connect P2 to the FMS port of the vehicle to get power/telematics and connect P4 to the Tachograph C port to read RTD data. |
| 2 | Tacho C is active/available but FMS is not active/available | Connect P2 of the FMS cable to the CAN sniffer harness (instructions -refer option 2) to get telematics/power and connect P4 to the Tachograph C port to read RTD data. |
| 3 |
FMS is available/active but Tacho C is sealed/not available
|
Connect P2 of the FMS cable to the FMS port of the vehicle — no tachograph connection needed. Go to Installation: RTD via the FMS Port (Scenario 3) section directly |
| Note: Confirm that remote download is enabled on the tachograph. If the fleet already uses a remote download service, it is enabled. If unknown, the only way to confirm is to connect to the vehicle. If RTD data is not available through either Tacho C or the FMS port, remote download is not enabled on the tachograph — the vehicle must visit an authorised tachograph workshop to enable it. |
Safety Precautions
Before starting the installation, ensure the following:
- The parking brake is engaged.
- The engine is off.
- The main power switch (if fitted) is turned off.
- The vehicle's ignition is completely OFF and the battery system is stable before taking any multimeter resistance measurements. This avoids false readings and protects the vehicle's ECUs.
Installation: Direct Tacho C connection (Scenarios 1 and 2)
Locate and extract the tachograph
- Locate the vehicle's tachograph unit.
- Carefully extract the unit from its dashboard slot using standard tachograph removal pins.
Check cable compatibility
- The FMS R02 cable is the standard cable. It does not include an integrated Y-splitter for Tacho C and is primarily used when the tachograph's C port is completely vacant. The cable has four labelled ends:
| Cable end | Description |
| P1 | Connects to the Motive vehicle adapter |
| P2 | Connects to the vehicle's FMS port |
| P3 | Optional: keeps the FMS port accessible for other uses. Required with Y-cable installations |
| P4 | Connects to the tachograph's C port (pins C5 and C7) |
| Note: If a third-party device is involved, an aftermarket Y-splitter may be required. |
Connect to Tacho C and verify termination
A CAN bus needs exactly two 120 Ω termination resistors, one at each physical end of the bus, giving a combined reading of approximately 60 Ω. Verifying this after connection is critical: incorrect termination causes signal reflection and unreliable remote downloads.
One of the two required terminations comes from the tachograph itself (engaged by the C7–C8 loop); the second must come from the truck's factory harness on the bus or, when the Tacho C port is vacant, from an added 120 Ω Tacho C resistor.
- Turn the ignition off.
- Check that the tachograph's C port is not sealed, and that you know whether any third-party device or factory cable is already connected to it.
- Connect the device: plug the Tacho C connector (P4 on the R02 cable) into the CAN C socket on the back of the tachograph. If another device or a factory harness already occupies Tacho C, connect both it and the R02 cable through the Tacho C Y-splitter.
- With the Tacho C cable connected, measure the resistance across pins C5 and C7 with a multimeter. Every installation must finish at approximately 60 Ω. Photograph the reading and add it to the job sheet for every installation.
- Use the measured resistance to determine whether corrective action is needed, per the sections below.
Scenario A: Tacho C is already populated (factory-fitted cable present)
Case 1 — resistance measures ~60 Ω after connection (properly terminated). No resistor is needed:
- Connect the Tacho C Y-splitter to the tachograph's C port, then connect one branch of the Y-splitter to P4 of the FMS cable.
- Add a loop between pins C7 and C8 of the Y-splitter end that connects to the tachograph.
- Attach the factory-fitted cable to the remaining open branch of the Y-splitter (skip if already done).
- Re-measure across C5 and C7 — the circuit must now read approximately 60 Ω.
Case 2 — resistance measures ~120 Ω after the Case 1 connection (under-terminated). Daisy-chain a second Y-splitter to create a third branch and add the 120 Ω resistor to one end:
- Y-splitter 1 (C7–C8 loop intact) connects to the tachograph. End 1 → FMS R02 cable; End 2 → Y-splitter 2.
- Y-splitter 2 connects to Y-splitter 1. End 1 → factory-fitted cable; End 2 → 120 Ω resistor.
- Re-measure across C5 and C7 — the circuit must now read approximately 60 Ω.
Scenario B: Tacho C is empty
Resistance measures ~120 Ω — under-terminated. Requires a 120 Ω termination resistor and a C7–C8 loop (to engage the tachograph's internal termination):
- Connect the Tacho C Y-splitter to the tachograph's C port, then connect one branch of the Y-splitter to P4 of the FMS cable.
- Add a loop wire between pins C7 and C8 on the Y-splitter harness that connects to the Tacho C port.
- Attach the 120 Ω termination resistor to the remaining open branch of the Y-splitter.
- Re-measure across C5 and C7 — the circuit must now read approximately 60 Ω.
| Note: When connecting to both the FMS port and Tacho C, the cable may be too short in some vehicles. If so, extend the Tacho C wire following Motive's recommended connection methods. |
Tacho C port pin reference
- C5 — CAN High
- C7 — CAN Low (measure resistance across C5 and C7)
- C7–C8 loop — engages the tachograph's internal 120 Ω termination
Installation: RTD via the FMS Port (Scenario 3)
This is a fallback approach only if Tacho C is sealed or caged.
Connect the FMS end of the cable (P2) to the vehicle's FMS port and complete the installation.
Refit the Tachograph
After all wiring is complete, carefully slide the tachograph back into its dashboard slot.
Next Steps and Support
- Enable the RTD feature and set up company cards in the Motive Fleet Dashboard, see the Motive Help Center for instructions.
- If remote download is not enabled on a tachograph, arrange a one-time activation at an authorised tachograph workshop.
- For installation support, contact Motive Support through your usual support channel.
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