Renault repair questions? Ask a mechanic for answers ASAP

Ask an Expert, Get an Answer ASAP!

Renault Megane Troubleshooting

What do the warning lights on your Renault Megane mean and what should you do about them? How do you deal with starting problems? Whether you plan to go to a shop or do your own repairs, knowing what is wrong and what repairs are required puts you in control of the situation. The insights of verified mechanical Experts will tell you what you need to know.

Read below to see some questions answered by Experts.

What does it mean if the Toxic Fume/Check Engine light is on (steady – not flashing) in a 2004 Renault Megane 1.9DCI with 82,000 miles?

Case Details: A scan in a local shop showed no stored fault codes. The vehicle is running perfectly.

The light remaining on steadily points to an engine or exhaust problem. Trial and error diagnosis may make the problem worse. A local shop will usually use a generic scanner and this will not be able to accurately read Renault fault codes. The vehicle should be taken to a dealer or specialist independent Renault shop to have the codes checked by a scanner. The problem could be exhaust related, but only a scan will identify the issue so the correct repairs can be done.

What could cause a 2001 Renault Megane 16V to intermittently crank but not start and what is the cheapest repair option?

Case Details: When it does start, it is without a problem.

The problem is commonly caused by a failing crankshaft position sensor. Cleaning it may resolve the problem for a short time but it will recur. Replacing it is the only long-term solution.

What could cause oil to mix with the water in a 2005 Renault Megane Cabrio and how can it be fixed?

Case Details: The engine block and cylinder head gasket have both been checked and neither is the cause.

Although the engine block and cylinder head gasket may appear to be okay, even a minute crack could cause this kind of cross-contamination. If not already done, a pressure test should be carried out to confirm that neither is the cause of the problem. If not, the likely cause is a faulty oil cooler that is part of the oil filter housing. Have it checked and replaced as required. If this is not the problem, then the oil and water seals on the thermostat should be checked and replaced if worn or damaged.

What could be the reason for a Renault Scenic to not start and a “Card Not Detected” message to appear?

This is a common problem on this model. It is usually due to a damaged card. These cards are very delicate. They have three soldered joints that hold the coil, which produces the immobilizer code to allow the vehicle to start, to the circuit board. Over time, the solder cracks and the coil connections are lost. It is possible to repair the card, but the soldering requires precision and delicacy. If repair is not possible, a new card will have to be purchased from a dealer who will also code it to the vehicle.

What could be the reason for the hazard lights on a Renault Megane 2.0T to always remain on?

Faulty hazard switches are a known issue on this model. Try tapping the switch firmly and jiggling it to see if the lights go off. If yes, then the switch is faulty and needs to be replaced. If not, the problem could still be the switch or it could be with the alarm system. Water ingress into the wiring and modules is another known issue and if this happens all kinds of problems could arise, including what is being experienced. The only way to determine what is wrong and what repairs are needed is to hook the vehicle up to a Renault scanner (generic scanners may not be able to read the fault codes correctly) to pinpoint the fault.

Is the clutch slave cylinder on a 2005 Renault Megane mounted inside the gearbox and if so, what is the reason for this unusual location?

The clutch slave cylinder on this model is inside the gearbox. It is what is known as a concentric slave cylinder and is part of the clutch release bearing assembly. This design eliminates the need for a clutch fork and so reduces the amount of force needed to press the clutch pedal. If the cylinder is to be replaced, the gearbox has to be removed from the vehicle.

How can the “Change Oil Soon” message be removed from the screen on a 2004 Renault Megane?

Case Details: The oil has been changed, but the message remains.

The procedure (for Keyless Entry) is as follows:

  • Insert the remote control in the ignition.
  • Do not touch the pedals.
  • Press and hold the START/STOP button for 10 seconds.
  • Press the right side stalk repeatedly until the wrench sign flashes and the odometer displays the distance remaining.
  • Press and hold the instrument cluster/panel button on the left side for 10 seconds.
  • The new service interval should be displayed. Release the cluster/panel button. Press the START/STOP button to turn the ignition off.

The service interval is now reset and the message should not appear. For vehicles without Keyless Entry, the same procedure should be used except that the key should be used instead of the START/STOP button.

What does it mean if the orange Engine Warning light and the Service light are on in a 2005 Renault Megane 1.5DCI that is running fine?

The Engine Warning light indicates that the vehicle’s computers have detected a fault in one or more of the systems. The fault may not directly affect vehicle functions but should not be ignored. With no obvious symptoms to work with, the only way to find what is wrong is to connect the vehicle to a scanner. While most shops have generic scanners that can read some codes, only a factory level scanner that dealers have will be able to read out complicated codes. The Service light indicates that the vehicle is due for service. The two lights illuminating at the same time may be a coincidence. Again, a scan will reveal the facts.

Being sure of what is wrong with your Renault Megane and how the problem can be fixed allows you to make informed decisions on how and where the repairs should be done. The opinions and recommendations of verified mechanical Experts will give you the guidance you need to make the right choices. You can go online, whenever you want, and ask Experts for personalized and clear answers to your questions.

Please type your question in the field below

3 verified Renault Mechanics are online now

Renault Mechanics on JustAnswer are verified through an extensive 8-step process including screening of licenses, certifications, education and/or employment. Learn more

I. Silva


High School or GED

25 positive reviews

Auto Mechanic

Vocational, Technical or Trade Scho

19 positive reviews


29 positive reviews
See all Renault Mechanics