ECU reference

A car has many control units. Some manage the battery or brakes; others handle climate control, lights or doors. Hanterill checks which ones respond when you connect. This guide explains what the units do and why one may be absent from a scan. The catalogue below names the control units Hanterill knows about on CMA cars. A listed unit is not necessarily fitted to every car.

How the module registry works#

The CMA module registry contains 49 control unit definitions:

• 44 modules have been observed and verified on live battery-electric vehicles.
• 40 modules support fault-code reporting.
• 5 modules (ref entries) represent combustion, hybrid, all-wheel-drive couplings, or air-suspension controllers that are only fitted on specific powertrains or trim levels. On a pure battery-electric car without air suspension, those five modules stay quiet, and Hanterill records their silence as expected rather than flagging a fault.

Every control unit has a unique network address on the vehicle network. You can think of this address like an office phone extension inside the car: one extension always rings the battery management unit, another always rings the climate controller, and another always rings the driver's door module. Hanterill sends its request to a specific extension, and that module answers directly.

Gateway modules#

Two modules sit between your laptop and the rest of the vehicle. The Vehicle Gateway Module (VGM) acts as the network router and firewall behind the diagnostic port, and the Central Electronic Module (CEM) acts as the main body computer and security coordinator.

Code	DoIP address	Name	Part number	Domain	UDS	DTCs
VGM	0x1002	Vehicle Gateway Module	36003604	Gateway	yes	yes
CEM	0x1A01	Central Electronic Module	32320214	Gateway	yes	yes

Reading identification data, sensor values, and fault codes through the gateway works in read-only mode without unlocking any security levels.

Energy and propulsion modules#

This group covers the high-voltage battery and electric drive system. The Battery Energy Control Module (BECM) monitors the high-voltage pack and individual cell voltages, the Vehicle Computational Unit (VCU) coordinates driver torque requests and driving modes, and the front and rear inverters (yarns/drive control modules) convert DC battery power into AC power for the electric motors and capture regenerative braking energy.

Code	DoIP address	Name	Part number	Domain	UDS	DTCs
VCU1	0x1602	Vehicle Control Unit 1	32350312	Energy	yes	yes
BECM	0x1635	Battery Energy Control Module	32290432	Energy	yes	yes
BMS	0x1B61	Battery Monitoring Sensor	not listed	Energy	yes	no
OBC	0x1634	On-Board Charger	36003389	Energy	yes	yes
IHFA	0x1692	Inverter High Voltage Front Axle	not listed	Energy	yes	yes
IEM	0x1637	Inverter ERAD Module	not listed	Energy	yes	yes
ECM	0x1630	Engine Control Module	not listed	Energy	yes	yes
TCMref	0x1632	Transmission Control Module	not listed	Energy	yes	yes
DEMref	0x1638	Differential Electronic Module	not listed	Energy	yes	yes
MVBMref	0x1652	Mid Voltage Battery Monitor	not listed	Energy	yes	yes
NRCMref	0x163D	Nox Reducing Control Module	not listed	Energy	yes	yes

Chassis and driver assistance#

Steering, braking, stability control, wheel angle sensors, and the cameras and radars that watch the road ahead and around the vehicle.

Code	DoIP address	Name	Part number	Domain	UDS	DTCs
BCM2	0x16A1	Brake Control Module 2	not listed	Chassis	yes	yes
PSCM	0x1612	Power Steering Control Module	not listed	Chassis	yes	yes
SAS	0x1616	Steering Angle Sensor	not listed	Chassis	yes	yes
SCL	0x1615	Steering Column Lock	32246209	Chassis	yes	yes
SUMref	0x1614	Suspension Module	not listed	Chassis	yes	yes
EGSM	0x1633	Electric Gear Selector Module	31492589	Chassis	yes	yes
IMS	0x1B52	Inertial Measurement Sensor	not listed	Chassis	yes	no
ASDM	0x1401	Active Safety Domain Master	not listed	Chassis	yes	yes
FLC2	0x1421	Forward Looking Camera 2	not listed	Chassis	yes	yes
FLR	0x1451	Forward Looking Radar	not listed	Chassis	yes	yes
WAM	0x1431	Wide-Angle Module	not listed	Chassis	yes	yes
PAC	0x1221	Park Assist Camera	not listed	Chassis	yes	yes
SODL	0x1432	Side Obstacle Detection Left	not listed	Chassis	yes	yes
SODR	0x1433	Side Obstacle Detection Right	not listed	Chassis	yes	yes

Cabin, body, and infotainment#

Displays, doors, seats, climate control, exterior lighting, airbags, telematics, and the keyless entry radio modules.

Code	DoIP address	Name	Part number	Domain	UDS	DTCs
DIM	0x1801	Driver Information Module	36003414	Cabin	yes	yes
CCM	0x1A11	Climate Control Module	not listed	Cabin	yes	yes
TCAM	0x1021	Telematics Connectivity Antenna Module	36003394	Cabin	yes	yes
SRS	0x1C01	Supplemental Restraint System	not listed	Cabin	yes	yes
IHU	0x1201	Infotainment Head Unit	36012873	Cabin	yes	yes
CSD	0x1241	Center Screen Display	not listed	Cabin	yes	yes
AUD	0x1212	Audio Module	32265526	Cabin	yes	yes
SWM	0x1B91	Steering Wheel Module	31674383	Cabin	yes	no
DDM	0x1A12	Driver Door Module	not listed	Cabin	yes	yes
PDM	0x1A13	Passenger Door Module	not listed	Cabin	yes	yes
POT	0x1A15	Power Operated Tailgate	not listed	Cabin	yes	yes
RML	0x1416	Rear Module Left	not listed	Cabin	yes	yes
RMR	0x1417	Rear Module Right	not listed	Cabin	yes	yes
HCML	0x1BB3	Headlight Control Module Left	not listed	Cabin	yes	yes
HCMR	0x1BB4	Headlight Control Module Right	not listed	Cabin	yes	yes
PXMR	0x1BBA	Pixel Module Right	not listed	Cabin	yes	no
PXML	0x1BBC	Pixel Module Left	not listed	Cabin	yes	no
OHC	0x1B22	Overhead Console	not listed	Cabin	yes	no
PAKM	0x1B31	Phone-As-Key Module	not listed	Cabin	yes	no
WPC	0x1B41	Wireless Phone Charger	not listed	Cabin	yes	no
BBS	0x1B51	Battery Backed-up Sounder	not listed	Cabin	yes	no
ESM	0x163A	Exterior Sound Module	not listed	Cabin	yes	yes

How Hanterill communicates with each module#

During a normal scan, Hanterill uses four standard diagnostic requests:

Read data values

Asks a module for a specific piece of information, such as its VIN, software version, or a live sensor reading.

Read fault codes

Asks a module for its stored, pending, or permanent Diagnostic Trouble Codes (DTCs) and their status.

Open diagnostic session

Places a module into its standard or extended diagnostic mode so its full set of sensors and identification records can be read.

Keep-alive heartbeat

Sends a quiet periodic pulse while a scan is actively running so modules do not go back to sleep mid-read.

From every module that answers, Hanterill reads a standard set of identity records:

Vehicle Identification Number (VIN)

Confirms the module belongs to the connected car and checks for mismatched replacement parts.

ECU serial number

Identifies the physical circuit board installed in the vehicle.

Hardware part and version

Shows the physical hardware revision reported by the supplier.

Software number and version

Shows the exact firmware currently running on the module.

Hanterill collects identity records from the modules that answer. The resulting inventory shows which hardware and software versions were read, and Firmware & Inventory can compare those records between visits. Check coverage before treating a missing module as removed.

Tools inside the ECU Registry screen#

When you select an individual module in the ECUs screen inside the app, you can:

• Inspect identity and fault counts: See the module's full name, network domain, answered software/hardware versions, and current fault count.
• Check security lock status (read-only): Query whether the module's protected maintenance levels are currently locked or unlocked without attempting to unlock them or changing anything on the car.
• Reset a single module: Send a targeted module restart command when you need to reboot one specific control unit after troubleshooting, behind an explicit confirmation dialog.

Modules with named readout groups show them on their detail page and in Module data. That includes the battery, gateway, display, climate, charger, engine and drive units. The Gateway screen shows security and diagnostic-access events, network and Ethernet histories, and resets with an odometer reading and reason where the car recorded them. Review the dates and coverage before drawing conclusions about a car's past.

Separate registries for SPA and SEA1#

The table above shows the 49-module CMA registry. SPA (41 catalogued modules) and SEA1 (25 catalogued modules) each maintain their own independent module registries. Hanterill never assumes a module address from one platform applies to another: each platform uses its own verified address map.

Why some modules stay silent#

Not every module in the catalogue is fitted to every car:

• No fault-code storage: Nine entries in the CMA catalogue answer identification reads normally but do not store fault codes of their own (DTCs: no). Hanterill skips them during fault scans rather than reporting an error.
• Optional equipment: Modules for air suspension, rear seat heating, a towbar, or a head-up display only answer on cars built with those options.