These instructions apply to the Toyota Hilux Mk8 facelift (AN120/AN130) 2021-2024.
For other models, please choose your vehicle here.
The facelifted eighth-generation Toyota Hilux (AN120/AN130 chassis, 2021 to 2024) hides a self-diagnosis mode inside its combination meter — the instrument cluster. It is the same family of test routine Toyota builds into most of its clusters, and it lets you check that every needle, warning lamp, indicator and segment of the LCD is working, and on many cars step through to stored fault codes and dealer customisation settings. It is opened with a specific ignition-and-button sequence rather than a scan tool, which makes it handy for a quick health check of the dash itself.
What the Hidden Menu Does
The combination-meter self-diagnosis mode runs the cluster through a full operation check. It sweeps the needles, lights every warning and indicator lamp in turn, and cycles the LCD so you can spot a dead segment, a stuck gauge or a bulb/LED that no longer illuminates. Stepping further into the menu exposes a diagnostic-trouble-code (DTC) display for faults the meter itself has logged, and a dealer-customise area where certain convenience settings can be changed. It does not reset service intervals or clear engine fault codes stored in other control units — it is a test and configuration tool for the instrument cluster.
How to Open the Hidden Diagnostic Menu
- Sit in the car with everything switched off. Have your hand ready on both the trip meter knob (the small button that toggles the odometer and trip readings) and the exterior lighting switch.
- Turn the ignition to ON (engine not running). The whole sequence that follows must be completed within a few seconds of this, so work briskly.
- Within about three seconds of switching on, move the lighting switch to the tail-light or headlight position, then press the trip meter knob three times.
- Turn the lighting switch back to OFF, and press the trip meter knob three times again.
- Move the lighting switch back to the tail-light or headlight position, and press the trip meter knob a further three times.
- The cluster enters self-diagnosis mode: the warning and indicator lamps, the needles and the LCD run through their operation checks, confirming you are in.
If nothing happens, the timing is almost always the cause — the steps are meant to be done in quick succession right after the ignition comes on. Switch off fully and try again a little faster.
Reading the Menu
Once in the mode, each press of the trip meter knob advances to the next check, and on many clusters a short buzzer confirms the press. The checks run in a set order — needle movement, needle indication, then the LCD display test — so you can watch each gauge sweep and each display element light up. Pressing the knob additional times steps into further modes: a further press typically switches to the DTC display so you can read any codes the meter has stored, and another moves to the dealer customise mode used to toggle certain settings. Note down anything that fails to light or move; a needle that does not sweep or an LCD segment that stays dark points to a cluster fault worth investigating.
Exiting Safely
To leave the self-diagnosis mode, simply turn the ignition OFF. That cancels the routine cleanly and returns the cluster to normal operation the next time you switch on. Because the mode only reads and tests the meter, exiting this way changes nothing on the car — unless you deliberately altered a setting in the dealer-customise area, in which case that change is retained. If you did adjust something and want to undo it, re-enter the mode and set it back before switching off.
Frequently Asked Questions
How do I open the hidden diagnostic menu on a 2021–2024 Toyota Hilux?
Turn the ignition ON, then within a few seconds cycle the light switch to on and press the trip button three times, switch the lights off and press three times, switch the lights on and press three times. The cluster then enters its self-test.
Does the hidden menu reset the service light?
No. The combination-meter self-diagnosis mode tests the cluster and can show meter-stored codes, but it does not reset the maintenance reminder. The service reset is a separate trip-button procedure.
Can the hidden menu damage anything on my Hilux?
No. The self-diagnosis and DTC-display functions only read and test. The only lasting change is if you deliberately alter a value in the dealer-customise area, which you can set back the same way.
Why won’t my Hilux enter the diagnostic mode?
Timing is the usual reason. The button and light-switch steps must be done quickly and in order right after the ignition switches to ON. Turn everything off and repeat the sequence a little faster.
If your Hilux has logged an engine fault code rather than just a cluster test result, you can look it up on autodtcs.com.
Independent guide — not affiliated with Toyota. Always follow your official service manual and safety precautions. Read our full disclaimer.