Stahlcar Classic Nissan Diagnostic Range
Full Consult I Diagnostics for Classic Nissan and Infiniti Vehicles
The Nissan Consult USB tool connects supported Nissan and Infiniti vehicles with the grey 14-pin Consult I diagnostic port to a Windows computer or compatible Android device.
With suitable software, it can read and clear engine fault codes, display detailed live ECU data, record road-test logs and perform selected active tests and adjustments on vehicles that pre-date standard modern OBD2 diagnostics.
Consult IGrey 14-Pin Nissan
Windows + AndroidUSB or Type-C OTG
Engine CodesRead and Clear
Live DataSensors + Switches
Data LoggingRecord and Replay
Approx. 1989–2000Some Later Models
Consult I is Nissan’s factory diagnostic communication system used across many vehicles during the 1990s. It is different from generic OBD2. A normal modern code reader may not connect to these vehicles at all, even when the car has electronic fuel injection and a check-engine light.
The interface contains the electronics needed to translate the Nissan Consult signal into a USB connection. It is not simply a cable with different plugs on each end.
Best Suited For
This tool suits owners, tuners and workshops working on classic Nissan and Infiniti vehicles with the original grey 14-pin Consult connector. It is particularly useful for diagnosing poor running, intermittent sensor faults, idle problems, ignition-timing issues and ECU warning codes on vehicles that are too old for modern OBD2 scanners.
The stable wired connection also makes it the preferred option for longer data-logging sessions and PC-based software functions.
What Consult I Can Show
The exact list depends on the engine ECU and software, but common live values may include:
- Engine RPM and vehicle speed
- Coolant temperature
- Airflow-meter voltage
- Throttle-position voltage or percentage
- Oxygen-sensor voltage
- Injector pulse width and calculated duty cycle
- Ignition timing commanded by the ECU
- Battery and charging voltage
- Auxiliary-air-control valve opening
- Short-term and learned fuel-trim information
- Fuel temperature where supported
- Switch, solenoid and idle-status information
Using Live Data for Fault Finding
Live data helps show what the ECU is seeing while the engine is running. This is more useful than simply reading a fault code when a sensor is inaccurate but has not failed completely.
For example, coolant temperature can be checked against the actual engine temperature, throttle position can be watched for a smooth change, airflow voltage can be monitored during acceleration and both oxygen sensors can be compared on a V-engine.
Ignition timing shown through Consult is the ECU’s commanded value. A timing light is still required to confirm the engine’s actual mechanical base timing.
A Fault Code Does Not Automatically Confirm a Failed Part
Older Nissan codes generally identify the circuit or signal the ECU considers incorrect. Dirty connectors, damaged wiring, poor earths and incorrect mechanical adjustment can produce the same code as a failed sensor.
Fault Codes and Self-Diagnostics
Compatible software can read the engine ECU’s stored self-diagnostic codes and display the code number and description without manually counting flashes from the ECU or check-engine light.
Codes can be cleared after the fault has been repaired. Some software also displays how many engine starts have occurred since the fault was detected where the ECU supplies that information.
If the fault remains active, the code will usually return after clearing.
Data Logging and Road-Test Analysis
ECUTalk and Nissan DataScan can record supported ECU values to a log file. This allows sensor information to be reviewed after a road test instead of requiring the driver to watch a laptop while the vehicle is moving.
Logs can help investigate faults that occur only under load, at a particular temperature or during acceleration. Nissan DataScan for Windows also includes replay and graph-analysis functions for comparing several values over time.
Depending on the software, data can be displayed as numerical values, gauges or graphs. ECUTalk can also calculate selected trip and fuel-use values when the correct injector size and engine information are entered.
Do Not Watch a Laptop While Driving
Use a passenger or record a data log for later review. Performance and acceleration tests should be carried out only in a safe and legal environment.
Windows PC Software Options
ECUTalk – Included Free Software
ECUTalk is a free lightweight Windows program and is the easiest place to start. It does not require a paid licence.
- Read ECU part number
- Read and clear supported engine codes
- Automatically detect available sensors
- Display selected data as full-screen gauges
- Metric and imperial units
- High-rate CSV data logging
- Automatic reconnection
- Derived trip and fuel-use gauges on suitable petrol vehicles
- ROM data download for reference
ConZult Free – Included Free Software
ConZult Free provides a simple alternative interface and is particularly associated with the Nissan 300ZX Z32.
- Basic live-data bar graphs
- Fault-code access on supported vehicles
- Base-idle mode for selected mechanical idle adjustments
Nissan DataScan I for Windows – Optional Paid Software
Nissan DataScan I provides the deepest general diagnostic package for this interface. It supports Windows XP through Windows 11 and is intended for factory Nissan ECUs using Consult I.
- Customisable live-data gauges and registers
- Data logging, replay and graph analysis
- Trip computer and acceleration testing
- Read and clear engine ECU fault codes
- Selected airbag diagnostics on supported models
- Selected HICAS diagnostics, logging and active tests
- Wideband oxygen-sensor integration with compatible external controllers
- ROM download and selected map tracing
Current Nisscan licence price: A$56.26 including GST as displayed on the developer’s Australian store.
Price checked 24 July 2026. The software developer controls future pricing and currency conversion.
Windows Active Tests and Adjustments
Nissan DataScan I and other compatible Windows programs can access selected active tests on supported engine ECUs. These allow the software to temporarily command or alter an ECU value while diagnosis or adjustment is carried out.
Depending on the vehicle and software, available functions may include:
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Cylinder Power Balance: Temporarily disables one cylinder at a time so its contribution can be compared.
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Fuel Pump Control: Switches the fuel-pump command on or off where supported.
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VCT Control: Commands the variable-cam-timing solenoid on suitable engines.
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Base Idle Adjustment: Temporarily disables ECU idle correction so the mechanical base idle can be set.
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AAC Valve Adjustment: Temporarily changes the idle-control valve command.
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Ignition Timing Adjustment: Temporarily changes the ECU timing command for diagnostic purposes.
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Coolant-Temperature Substitution: Temporarily changes the temperature value used by the ECU for testing.
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Clear Self-Learn: Clears selected learned fuel-trim information.
Active Tests Require Care
These functions can change how the engine runs. Excessive temporary fuel or ignition changes can damage the engine.
Use active tests only when the purpose and correct procedure are understood. All modified values return to normal when the test is stopped, the interface is disconnected or the engine is restarted.
Android Operation with the Type-C Adapter
The included USB Type-C OTG adapter allows the Consult USB interface to connect to a compatible Android phone or tablet that supports USB Host or OTG operation.
The recommended Android software is Nissan DataScan I, also called NDSI. The app is designed specifically for factory Nissan and Infiniti ECUs using the grey 14-pin Consult I connector.
NDSI Android Functions
- Read and clear supported engine ECU codes
- Real-time engine sensor display
- Customisable dashboard gauges
- Engine data logging
- Video recording with a matching data-log file in the paid version
- Petrol and diesel Consult I support
NDSI Android App Costs
NDSI Lite: Free, advertising-supported version for checking connection and basic functions.
Full NDSI app: The current Google Play listing shows US$6.99 as a one-off purchase.
Price checked 24 July 2026. Google Play may display a different local-currency amount, and the developer controls future pricing.
Android Has Fewer Functions Than Windows
The Android app communicates with the engine ECU only. Windows Nissan DataScan I provides the deeper active tests, adjustments, replay tools and selected access to additional modules such as airbag and HICAS.
USB Driver and COM-Port Setup
Windows treats the interface as a USB serial port. The correct driver must be installed before the diagnostic software can communicate with it.
- Install the supplied USB driver before connecting the interface where possible.
- Connect the Consult interface to the computer.
- Open Windows Device Manager and locate the USB Serial Port under Ports (COM & LPT).
- Note the assigned COM-port number.
- Select the same COM port inside ECUTalk, ConZult or Nissan DataScan.
- Connect the grey 14-pin plug to the vehicle.
- Turn the ignition on or start the engine. The Consult connector is normally not powered in the accessory position.
- Start communication through the software.
Older software may require a low COM-port number. If the program cannot see the interface, assigning an unused port between COM2 and COM6 often resolves the problem.
Most Connection Problems Are Setup Related
Common causes include the wrong COM port, missing driver, ignition left in the accessory position, a blown vehicle fuse, unsupported ECU or selecting the wrong software protocol.
The supplied Stahlcar setup guide includes the software-download and COM-port instructions.
Vehicle and Connector Compatibility
The first check is the physical connector. Compatible vehicles normally have a grey female 14-pin Nissan Consult connector near the driver’s fuse box, kick panel or lower dashboard.
Most supported vehicles were manufactured from approximately 1989 to 2000, although some later vehicles continued using the Consult I protocol.
Common applications include selected Skyline, Silvia, 180SX, 200SX, 300ZX, Pulsar, Primera, Maxima, Bluebird, Stagea, Laurel, Terrano, Pathfinder, Patrol, Navara, Elgrand and related Nissan or Infiniti models.
Do Not Order by Vehicle Year Alone
Not every Nissan from the 1990s uses Consult I. Confirm the actual connector before ordering.
- Not compatible with the older black 12-pin Nissan diagnostic connector
- Not compatible with normal 16-pin OBD2 or Consult II vehicles
- Not compatible with CA18-powered vehicles that do not use Consult
- Selected A31 Cefiro RB20 vehicles do not use the Consult system
- Some late vehicles have both connectors but use Consult only for secondary systems
Factory and Modified ECU Compatibility
The interface is designed for a factory Nissan ECU using the original Consult I communication circuit.
Remapped factory ECUs, daughterboards and piggyback controllers normally retain the factory diagnostic connection. Fully replacement standalone ECUs such as PowerFC units generally do not support Nissan Consult communication unless the ECU manufacturer specifically provides it.
The cable can also be used as the Consult communication interface for NIStune diagnostic and tuning software when a compatible NIStune board and separate software licence are installed.
The Cable Does Not Tune a Standard ECU
Consult allows diagnosis, monitoring and selected temporary active tests. Permanent fuel and ignition map changes require suitable ECU hardware and separate tuning software such as NIStune.
Diagnostic Limits
This is not a modern all-system scanner. Engine ECU coverage is the main function.
Windows Nissan DataScan I can access selected airbag and HICAS systems on compatible vehicles, but the interface does not provide universal ABS, transmission, climate, immobiliser, key programming, service-reset or body-control coverage across every Nissan.
It cannot diagnose later Consult II or CAN-based vehicles and cannot perform dealer ECU programming.
What’s in the Box
- Nissan Consult I USB diagnostic interface
- USB connection cable
- USB Type-C OTG adapter for compatible Android devices
- ECUTalk free Windows software download
- ConZult Free Windows software download
- Driver download and setup guide
USB or Bluetooth Consult Tool?
Choose the USB version for the most stable Windows connection, longer data-logging sessions, Nissan DataScan PC functions and Type-C Android operation through the included OTG adapter.
Choose the Bluetooth version when wireless Android operation is the priority and the deeper Windows active-test functions are not required.
