Honda Grace GM4 warning lights: what each one means
17 warning lights from Honda's own owner's manual, grouped by how urgently the manufacturer says to act, with the printed page or original web section for each so you can check the original.
Japan Grace Hybrid GM4, front-wheel drive, only as described in manual 30T9E6200. The document footer is dated 25 May 2017; that is document provenance, not evidence that every GM4 production year has this equipment. Match the actual cluster, messages and options. ACC/LKAS depend on fitted Honda Sensing equipment. No GM5 AWD, petrol Grace or other Honda chassis applicability is inferred. Manufacturer first actions do not identify a failed part.
A warning light is the car reporting a condition, not a diagnosis of a specific part. If braking, steering or engine behaviour changes, stop where it is safe. If you are unsure, follow the manual and contact a dealer. This page does not replace a professional inspection.
The manufacturer says to stop somewhere safe straight away, or to stop if specific symptoms occur.
Red brake warningStop safely now
Manual name: ブレーキ警告灯（レッド） · red · printed p.65, 355
When it lights
Normal brief power-ON check or an applied parking brake; it can also indicate low brake fluid or a brake-system fault.
What the manual says to do
If it lights while driving or remains after parking-brake release, gently check brake-pedal resistance and the fluid level; obtain Honda repair immediately.
With no pedal resistance, stop immediately somewhere safe, shifting down if necessary. With ABS also lit, avoid high speed and sudden braking. With the orange brake-system warning also lit, stop immediately somewhere safe and press the pedal firmly if it feels hard.
Low engine-oil pressureStop safely now
Manual name: 油圧警告灯 · printed p.66, 353
When it lights
Lubricating-oil pressure falls while the engine is running, separate from the normal power-ON check.
What the manual says to do
Stop immediately on level ground somewhere safe and turn on the hazard lights. Stop the power system and wait about three minutes before checking oil level; add oil if required.
Honda then says to start the power system and check the lamp. If it does not go out within ten seconds, stop the power system and request immediate Honda repair. Running with low pressure can damage the engine.
12V battery charging warningStop safely now
Manual name: 12V バッテリー充電警告灯 · printed p.66, 354
When it lights
The 12V battery is not being charged.
What the manual says to do
Stop somewhere safe and request Honda repair immediately. Reduce consumption by switching off air conditioning, rear demisting and similar loads.
When stopping temporarily, this manual says not to stop the power system: restarting uses the 12V battery and may become impossible. This is not permission to keep driving or a diagnosis of battery size or condition.
Transmission / shift-position warningStop safely now
All positions may light briefly during transmission adjustment, when temporary acceleration is unavailable; normal operation resumes after the display clears.
A flashing selected position indicates a fault; selected or all-position flashing can accompany inability to drive or to select P.
What the manual says to do
For the selected-position fault, avoid sudden starts and acceleration and obtain Honda inspection immediately.
If the vehicle cannot drive, stop immediately somewhere safe and contact professional assistance. When parked, apply the parking brake securely, particularly if P cannot be selected. Follow the actual message and original manual rather than repeatedly trying to force a gear.
High coolant temperature: flashing versus steadyStop safely now
Manual name: 高水温警告灯（レッド） · red · printed p.71, 351–352
When it lights
Flashes as engine-coolant temperature rises; steady red illumination indicates a further rise. The normal blue cold-engine indication is a different state.
What the manual says to do
If flashing while driving, slow down. If steadily illuminated, stop immediately somewhere safe and cool the engine using this edition's overheating procedure.
Do not open a hot cooling-system cap or expose yourself to steam. Consult the original procedure and obtain professional help if uncertain.
Have it inspected promptly
The manufacturer says to have the car inspected by a dealer promptly.
PGM-FI: steady versus flashingHave it inspected promptly
Manual name: PGM-FI 警告灯 · printed p.66, 354
When it lights
Steady illumination indicates a possible emissions-control fault; flashing indicates detected engine misfire.
What the manual says to do
For steady illumination, avoid high-speed driving and obtain Honda inspection immediately.
For flashing, stop somewhere safe away from combustible material and stop the engine for at least ten minutes. If it flashes again after restarting, Honda limits the trip to the nearest dealer to 50 km/h or less. Do not transfer this instruction to another manufacturer or chassis.
A fault in electric-servo braking or another brake-related system; the table separately describes hill-start-assist failure.
What the manual says to do
If lit while driving, obtain Honda inspection immediately. The manual says ordinary braking remains with this warning alone; a simultaneous red brake warning requires stopping.
Hill-start assistance does not operate if its fault is reported; arrange Honda inspection.
VSA intervention versus faultHave it inspected promptly
Manual name: VSA 警告灯 · printed p.70
When it lights
Flashes during VSA intervention; steady illumination can indicate a brake-assist, VSA or hill-start-assist fault.
What the manual says to do
For a persistent fault while driving, obtain Honda inspection immediately. Do not confuse normal intervention flashing with the steady fault state.
Honda Smart Key system warningHave it inspected promptly
Manual name: Honda スマートキーシステム警告灯 · printed p.70
When it lights
A Smart Key system fault, including illumination while driving, failure to go out after power-system start, or abnormal indications around power OFF.
What the manual says to do
Obtain Honda inspection immediately for the abnormal states listed in the manual. This system warning alone is not proof that replacing the key coin cell will fix it.
Electric power-steering warningHave it inspected promptly
An EPS fault. The manual also notes that revving the engine while stationary may illuminate it and make steering heavy.
What the manual says to do
Stop somewhere safe and restart the engine as Honda directs. If the indication remains afterward, obtain Honda inspection immediately.
Power-system warningHave it inspected promptly
Manual name: パワーシステム警告灯 · printed p.72
When it lights
A power-system fault after its normal brief power-ON check.
What the manual says to do
If it lights while driving, obtain Honda inspection immediately. The warning does not identify which hybrid component has failed.
ACC warningHave it inspected promptly
Manual name: ACC（アダプティブクルーズコントロール）警告灯 · orange · printed p.72 · fitted on some grades only
When it lights
A fault in the fitted adaptive-cruise-control system.
What the manual says to do
If it lights while driving, obtain Honda inspection immediately. Do not assume the assistance remains available.
LKAS warningHave it inspected promptly
Manual name: LKAS（車線維持支援システム）警告灯 · printed p.72 · fitted on some grades only
When it lights
A fault in fitted lane-keeping assistance. Persistent illumination or failure to light during its check is abnormal.
What the manual says to do
Obtain Honda inspection immediately. This reference is not a camera-calibration or steering repair procedure.
Check and correct
Often caused by something you can check or correct yourself; see the conditions listed.
Seat-belt reminderCheck and correct
Manual name: シートベルト非着用警告灯 · printed p.68
When it lights
The driver or front passenger is not belted; the lamp can flash while the warning buzzer sounds.
What the manual says to do
Fasten the belt correctly. If it remains on with belts correctly worn, the manual notes possible sensor misdetection or another cause; do not disable the reminder.
Information
Status information.
VSA OFF statusInformation
Manual name: VSA OFF 警告灯 · printed p.70
When it lights
Comes on when VSA is switched off, separate from its brief power-ON check.
What the manual says to do
Check the actual switch state and the manual's VSA section. This indicator by itself is not evidence of a failed VSA component.
Related ownership guides
Follow the warning's first action above. These service references do not diagnose or clear a warning.
Source: Honda Motor Co., Ltd., Japan Grace Hybrid manual 30T9E6200; document footer dated 25 May 2017. Open the original manual ↗ (Japanese). English wording on this page is a CarFactBook paraphrase of the manual, checked on 2026-10-27.
