Volvo Trucks VNM Dash Warning Lights: Symbols and Meanings

The Volvo Trucks VNM's instrument cluster provides real-time alerts tailored for heavy-duty operations. This guide explains the VNM-specific symbols and actions to ensure safe and efficient driving.

How to read the colors: Red symbols demand immediate attention—stop the truck when safe. Amber warns of service needs or system faults; green/blue indicate active functions or systems engaged.

Volvo Trucks VNM Warning Light Symbols

SymbolNameColorWhat it meansWhat to do
Master Warning (Stop)REDA serious fault is detected that requires immediate engine shutdown to prevent damage on your VNM.Safely pull over, shut down engine, and contact Volvo service.
Master CautionAMBERA non-critical system fault has been logged in the VNM's electronic control unit; check the message center.Drive to a service facility at your earliest convenience.
Check Engine (MIL)AMBERThe VNM's emissions control system requires attention; reduced fuel economy may occur.Schedule diagnostics with a Volvo dealer; avoid extended idling.
Engine Oil PressureREDOil pressure is critically low in the VNM's D13 or D11 engine, risking internal damage.Immediately stop the engine and check oil level; do not restart.
Battery / ChargingREDThe VNM's alternator is not charging or the battery voltage is too low.Inspect alternator belt and connections; call roadside assistance.
Coolant TemperatureREDEngine coolant temperature exceeds safe limits on your VNM; continued operation may cause damage.Pull over, idle engine to cool, check coolant level.
ATTransmission TempAMBERThe I-Shift transmission fluid is running hot in the VNM; reduce load or speed.Shift to a lower gear and avoid heavy throttle until temperature drops.
Brake SystemREDA fault in the VNM's brake system reduces stopping capability; might be low air pressure.Stop safely, check air pressure gauges, and inspect for leaks.
ABSABSAMBERThe antilock brake system on your VNM has a fault; standard brakes still work but without ABS.Drive cautiously and have the ABS serviced soon.
PParking BrakeREDThe parking brake is engaged on the VNM; do not drive unless released.Release the parking brake before moving.
Tire Pressure (TPMS)AMBEROne or more tires on your VNM are significantly underinflated, affecting fuel economy and safety.Check tire pressures and inflate to recommended levels.
Glow Plug / PreheatAMBERThe VNM's intake heater is active to aid cold starting; wait for the light to go out.Wait until the light extinguishes before cranking the engine.
DPF / RegenerationAMBERThe diesel particulate filter on your VNM needs a parked regeneration to clear soot buildup.Park, engage parking brake, and press the regen switch.
DEF / AdBlueAMBERDiesel exhaust fluid level is low on the VNM; engine power may be reduced if ignored.Refill DEF at the next stop; use Volvo-approved fluid.
Water in FuelAMBERWater has accumulated in the VNM's fuel filter/water separator; drain promptly.Open the drain valve on the fuel filter housing to remove water.
Low FuelAMBERThe VNM's fuel level is below 15% of tank capacity.Refuel as soon as possible to avoid running out.
High BeamBLUEThe high-beam headlights are activated on your VNM.Dim when approaching other vehicles.
AIRAir Brake Pressure (Low)REDAir brake pressure in the VNM is below 60 psi; brakes may not apply fully.Stop immediately and allow air pressure to build; check for leaks.
EBEngine / Exhaust BrakeGREENThe VNM's engine brake or exhaust brake is engaged to assist downhill speed control.The brake is active; no action needed.
TrailerGREENA trailer is detected and connected to the VNM's electrical system.Verify trailer lights before departure.
High Exhaust Temp (HEST)AMBERThe VNM's exhaust aftertreatment system is hot; avoid parking on dry grass.Park only on paved surfaces until the light goes out.

21 symbols shown. Icons follow ISO 2575 dashboard standards; exact graphics vary by model year.

Most Important Warning Lights

Engine Oil Pressure Low

Common causes

  • Low oil level
  • Oil pump failure
  • Oil pressure sensor fault

What to do

On your VNM with a D13 engine, immediately stop the engine. Check the oil level using the dipstick; if low, add oil of the correct viscosity. If level is fine, have the oil pressure system inspected by a Volvo technician before restarting.

Coolant Overheating

Common causes

  • Low coolant level
  • Broken thermostat
  • Cooling fan malfunction

What to do

Pull over and idle the VNM to allow the electric fan to cool. Check coolant level in the degas bottle; add Volvo-approved coolant if needed. Do not open the hot radiator cap. If light persists, tow to a Volvo service center.

Low Air Brake Pressure

Common causes

  • Air system leak
  • Failed air compressor
  • Governor malfunction

What to do

Stop the VNM immediately. Let the engine run to build pressure; if pressure does not rise above 60 psi, inspect air lines and fittings for leaks. A failing air compressor may require replacement by a Volvo dealer.

Battery Charging Failure

Common causes

  • Faulty alternator
  • Loose or corroded battery cables
  • Broken serpentine belt

What to do

Turn off unnecessary electrical loads. Check the alternator belt on your VNM for tension; if loose, tighten or replace. Clean battery terminals. If the light stays on, have the charging system tested at a Volvo shop.

Transmission Overheat

Common causes

  • Overloaded truck
  • Low transmission fluid
  • Cooler blockage

What to do

Reduce speed and shift the I-Shift to a lower gear. Avoid stop-and-go traffic. Check transmission fluid level with the engine running at idle. If low, add Volvo transmission fluid. Have the cooling system inspected if overheating persists.

Frequently Asked Questions

Why does the amber DPF regen light stay on for so long in my VNM?

The VNM's DPF requires a parked regeneration when soot load exceeds 80%. After pressing the regen switch, the process can take 20–40 minutes. Ensure the truck is parked on a non-combustible surface with the parking brake engaged.

What should I do if the red brake system light comes on while driving?

Immediately reduce speed and pull over. The VNM's brake system may have lost air pressure. Check the air gauges; if below 60 psi, wait for the compressor to build pressure. If pressure doesn't rise, call for service.

How do I clear the water-in-fuel light on my VNM?

Locate the fuel filter/water separator on the driver side of the engine. Open the drain valve at the bottom until clear fuel flows, then close. The light should reset after a few minutes of running.

Can I continue driving with the amber check engine light on?

Yes, but the VNM may enter derate mode to protect the engine. Reduce load and schedule a diagnostic scan at the next Volvo dealer. Prolonged driving could cause damage or emissions issues.

Why does the DEF light come on even after refilling?

The VNM's DEF system uses a quality sensor. If non-standard fluid was added, it may not be recognized. Use only Volvo-approved AdBlue. Also ensure the tank cap is tight; air in the system can cause false warnings.

What does the green trailer symbol mean on the VNM dashboard?

It indicates the VNM's electronic control unit has detected an electrical connection to a trailer. Verify all trailer lights are working before departure. The light remains on as long as the trailer is attached.