These instructions apply to the Vauxhall Astra Mk7 (K/B16) 2015-2021. For other models, please choose your vehicle here.
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The Vauxhall Astra (Mk7/K, 2015–2021) — the last Astra built on a General Motors platform before the PSA era — keeps the classic Vauxhall hidden test menu. You can open it from the factory IntelliLink screen with a button combination, no scan tool or app required, and read out diagnostic values such as battery voltage, coolant temperature and the unit’s hardware and software versions.
What the Hidden Menu Is and What It Shows
This is the engineering readout built into the IntelliLink/Board Computer system. On the Astra K the screens typically include:
- Battery voltage measured at the display.
- Engine coolant temperature as a live figure.
- Head-unit / display temperature and the dimmer level.
- Hardware version, software version and build date of the screen and trip computer.
- A digital speedometer and trip-computer data pages.
The pages are read-only diagnostic screens — you cannot alter a setting or harm anything by browsing them.
How to Open It
- Turn the ignition on and let the IntelliLink display wake up.
- Press and hold the SETTINGS (or MENU) button together with the radio power/volume knob until the screen switches into the hidden test menu. Some cars respond to holding the volume-knob button and the centre MENU button together.
- When the engineering screen appears, release the buttons.
Reading Voltage, Temperatures and Codes
Once in, use the BC (Board Computer) button to step through the screens. The battery-voltage page should read about 13.8–14.6 V with the engine running on a healthy charging system, and roughly 12.4–12.7 V at rest. The coolant page gives you a real temperature number rather than just the dashboard gauge. If any page displays a fault reference, jot it down to decode afterwards.
How to Exit
Press the SETTINGS, MENU or back button to return to the normal IntelliLink display, or simply switch the ignition off. Nothing is saved and nothing is changed — the menu is purely a viewer.
Frequently Asked Questions
Does the Astra K hidden menu need a diagnostic tool?
No. It is a built-in factory menu opened with a button combination on the standard IntelliLink head unit — no scanner, cable or app.
Will it work with an aftermarket stereo?
No. The menu is tied to the factory IntelliLink unit. If the original head unit has been replaced, the combination will not open it.
Can browsing the menu damage anything?
No. Every page is read-only. You cannot change a setting, reset the service light or clear codes from here.
What battery voltage is normal?
About 12.4–12.7 V engine off, and roughly 13.8–14.6 V engine running. A running figure under about 13.5 V suggests a charging fault.
Can I read full fault codes here?
The menu shows engineering values and any unit-stored references, not a complete OBD scan. If a code appears, look it up on autodtcs.com.
If one of the diagnostic pages shows a fault reference, find out what it means on autodtcs.com.
Disclaimer: The information on this page is provided for general guidance only. Always follow your official service manual and safety precautions when working on your vehicle. We are not responsible for errors, omissions, or any damage resulting from the use of this information.
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