Renault Forums :: Independent Renault forum - View Single Post - Renault - Clio - Starting Problems - A solution???

View Single Post
post #141 of (permalink) Old 9th June 2016
Join Date: Jun 2016
Posts: 77
Nominated 5 Times in 2 Posts
Nominated TOTW/F/M Award(s): 1
Thanks: 2
Thanked 20 Times in 19 Posts
Re: Renault - Clio - Starting Problems - A solution???

Originally Posted by stormcoat View Post
I have tried every solution to this intermittent failure to start on our Clio mk2 1.4 16v without success. The car will perform admirably for several days, then, without any warning, will fail to fire up, even though the starter turns at full speed.

Eventually, sometimes after trying all the recommended tricks with the key and sometimes with no tricks at all, the engine fires and runs perfectly.

I have succeeded in connecting my laptop to the car and can obtain a running log, which shows most readings, such as rpm, oxygen sensor, temperature etc, in real time, but no fault code shows up, even when I disconnected the MAP sensor to prompt the ecu into logging a PID.

I do not have a spare key.

I have been in contact with Ian, at who has been very generous with his time in replying with many suggestions. I would like to thank him and, should anyone need an immobiliser bypass, he is the one to go to.

Unfortunately (?) my red disc LED immobiliser light on the dash is not flashing when the key is inserted or turned, which suggests that my problem is caused by something else, otherwise I should not hesitate to fit a bypass.

My nearest Renault franchise is 15 miles distant and, besides, is not confident of finding any cause within an affordable time (£60per hour!) They say that the chances of finding an intermittent fault while the diagnostic system is connected are, understandably, not great.

My only hopes of curing this are finding, either, someone on this forum who has found and remedied a cause not yet recorded on the forum, so far, or finding an independent garage, with Renault capability, who has done the same.

So far, I have:

* checked all visible connections, except the Lambda sensors underneath the vehicle. (I shall do this next, but don't hold much hope of finding a loose wire.)

* removed and tested all relays in the fuse box under the bonnet.

*removed, cleaned and replaced the crankshaft sensor and found both it and its connections to be perfect.

* disconnected the non standard Sony radio.

* tried all the key tricks, including leaving the ignition on for ten to twenty minutes.

The car often starts after any of these procedures, leading me to believe that they have worked, until it fails the next time. It even "responded" to squirting WD40 on all visible connections, for a while.

if someone can help and I can cure the problem, I shall take care to record everything I learn, on the forum, for the benefit of others.

Members of my family are becoming exasperated and are looking to buy another (second hand, old) car. Are we just going to buy yet another set of problems? Or are there used vehicles out there which are less likely to be so temperamental or difficult to diagnose with generic OBD equipment?
As no-one is giving you any suggestions; I thought I'd make a summary of the previous 140 posts made in this thread. Here goes nothing.

First of all, about the immobilizer light, there are a few different situations.

1. How it normally operates when everything is working:
Immobilizer light at blinks at 1 Hz frequency with no key in the ignition lock. You put the key in and turn the key one position ahead, such that the power is on. The immobilizer light now glows constantly red. Turn the key one position more to crank the engine. The immobilizer light goes off and the engine fires up.

2. Immobilizer light is not flashing at all when there is no key in the ignition lock. The UCH is not receiving power or it is faulted.

3. Immobilizer light flashes at 4 Hz (=faster than the normal rate). This is to say that the UCH is not recognizing the key as an authorized key to start the engine. Probably engine will not rotate or will rotate for a couple of times and then stop rotating. Problem with the key fob (dried/cracked/bad/non-conductive soldering joints on the components of the key fob PCB) or the key detector ring around the ignition lock base is, for some weird reason, broken. Or the UCH is broken. Or something else.

4. Immobilizer light stays lit when cranking the engine. This indicates a problem in the data transfer between the UCH and the ECU . Probably a corroded/broken wire in the loom connecting the ECU and the UCH , or the UCH itself has an internal fault. Or something else.

Short legend:
1. UCH = body electrics control module, controls everything except the under-bonnet stuff (the ECU handles the under-bonnet).
2. wiring loom = just a bunch of wires usually taped together with black tape

Some problems that were found to rectify the starting issue discussed in this topic, the order is such that I personally feel number one would be the most common and so on.

Always read the OBD2 fault data first! Order a cheap OBD2 bluetooth adapter from anywhere online ( ebay , and acquire, for example, the Torque Pro Android software. You can get it from Google Play Store. Install the software and read your OBD2 codes with your phone. This costs around 10 euros in total. Investment which pays out after the first time you would need to bite the bullet and let a repair shop read the codes for you. These OBD2 adapters usually require pairing with the phone through the Bluetooth menu of the phone and the pin code for this is usually 1234 or 0000.

1. The key fob has a problem.
- The key PCB soldering has gone dry/corroded. (engine turns over but will not fire, immo light flashes at 4 Hz when trying to start) try with a spare key, if it makes no difference -> not a problem with the keys.
- Apparently cleaning the original key blade has helped some people. Personally I do not believe in this working at all, but it is possible that the key blade acts as an antenna for the decoder ring located around the ignition lock base. Or then it is just the dried joints
- Check out this thread to get an idea about what you are looking for if you decide to try to tackel the dry joints yourself. The key is not for a Clio but the principles are exactly the same: Megane II - Keycard repair instructions / development
- There is possibly a chip inside the key which needs to sit in its proper holder. If the key makes a rattling sound when shaken, this chip has gone loose.
- Some people report that changing the key fob battery (type: CR1220) has helped. (Personally, I think the battery should not be even required in the key for the car to start but it might depend on what year your Clio is, maybe the older ones require a battery inside the key fob).
- Not 100 % sure about this, but: Changing the key fob battery will not fix the problem if the engine is cranking over just fine, i.e., the immobilizer light is not blinking at rapid pace (4 Hz) and preventing the engine from cranking.

2. Crankshaft position sensor is broken or more likely just dirty (according to many people who got it working just by cleaning the sensor). Or wiring of the crank position sensor is busted.
- Should not stop the engine from cranking.
- Check for visual problems on the wiring beginning at the sensor.
- Cleaning: electronics cleaning spray/q tip/scouring pad/soft wire brush
- Location: at the end of the engine, behind a coolant tube. Kind of a half moon shaped piece of metal with wires going to it. Look through the topic to see pictures of it. It is really easy to replace yourself after you find it.
- Symptoms: Intermittent periods of the car not firing up. Sometimes the engine just shuts off while driving.
- How to diagnose: Remove a spark plug and hold it in the imminent vicinity (1 centimeter or closer) of any metal part of the engine block. Not touching directly the metal though, but in the air! Get someone to crank the engine by turning the key. If a spark jumps from the plug to the metallic engine block, then the crankshaft position sensor (a.k.a. TDC a.k.a. top dead center sensor) is supposedly working.
- When doing the spark plug test, wear rubber gloves or you will feel the spark on your hands. One alternative is to stick a screwdriver into the HT lead and hold the screwdriver near the metallic engine block. The 20 000 volt spark does not require a spark plug attached to the HT lead to jump onto the engine block.

3. Fuses have a bad contact in the engine bay fuse box or in the interior(located on the side of the dashboard under a small panel) fuse box.
- Engine bay problems are thousand times more likely, unless your sunleak is leaking water into the dashboard.
- Repairing is done one fuse at a time: Pull out - plug back in - rinse crap away with electronics cleansing spray if deemed necessary.
- Also inspect all fuses that they are not burnt. (That the wire inside the transparent plastic case is not broken)

4. UCH fault
- A tell-tale symptopm is a constant clicking/chattering of relays underneath the dashboard. Although, if the battery is totally empty this will also happen.
- More tell-tale symptoms include intermittent irrational operation of some or all of the following: blinkers, wipers, headlights, electric windows, dashboard backlight, interior light, etc.
- If a problem exists, it will present itself more often in the winter temperatures. (for some odd reason) (this has been confirmed from a Renault dealer)
- Another tell-tale symptom is if the car hesitates to lock the doors via remote. Such that the car will flash its blinkers (as a signal that doors have been locked) but the doors will instantly unlock again.
- If there is no red immobilizer light flashing (slow pace, a.k.a., at 1 Hz) with no key in the ignition lock, then the UCH is not receiving power or is otherwise broken.

5. Black (there are 2...3 similar black small ones) relays inside the engine bay fuse box. Switch their locations between each other to troubleshoot if the relays itself are at fault.
- After altering the locations of the relays, try to start the engine and inspect if there is any clear alteration in the behaviour of the immobilizer light, etc.
- Squirt a liberate amount of electronics cleaner to clean the fuse box base from road dirt.
- Visually inspect the wiring near the fuse/relay box for problems.

6. The engine earth strap has come loose or is corroded and thus broken.
- Located near the gearbox in the engine bay.
- Connects the engine to the chassis of the car.
- A braided cable about 1 inch thick.
- If you can push start the car just fine, this is definitely a possible cause of starting problems as the starter motor power goes through this cable and if it is corroded badly enough, then the starter might not budge!

7. Problem with the starter motor
- The starter motor got stuck. (Put the car in 3rd gear and rock it back and forth) (smack the starter motor with a hammer -> start up fine -> starter needs to be looked at)
- The starter motor cables have corroded and are not conducting.
- Detach the starter wires from on top of the starter motor and clean all mating surfaces using a soft wire brush or something similar.
- Re-attach all wiring in correct places.
- Symptom reported by a poster: The car won't start when hot, needs to cool down for 10-20 minutes --> possibly a corroded connection on the starter motor. The heat from the engine thermally expands a nut, under which a cable is attached and the contact is lost until the bolt cools off and regains the pressure onto the connector, or something like that.

8. Problem with the fuel pump
- May be at fault if the car sometimes starts, sometimes does not.
- Push in the red button on the fuel pump, which is a crash activated emergency fuel pump cut-off feature.

6. Random wiring loom fault somewhere (can be impossible to pinpoint exact location)
- Wires between the UCH and ECU are busted.
- A constant red immobilizer light stays on, when you try to crank the car.
- A Renault CLIP device can be utilized to troubleshoot these wiring loom problems, contact a garage who does Renault repairs
- Possibly also wires from battery to ECU are corroded. Check the battery cables that they are secured in place tightly.

7. Engine coolant sensor is broken.
- Starting problems appear most likely only when the engine is hot.

8. The decoder ring around the ignition lock base
- Very unlikely to get broken if not have been manhandled with a screw driver.

Random stuff people had successfully started their Clio with:

1. Keep the key fob button pressed while turning the key to crank the car. (Someone could explain why this has worked on many occasions...!?)
2. Put on the ignition without cranking, leave key in for 30 seconds, take out key, lock doors, open doors and the car will now fire up when cranked.
3. Quote: "Whilst in ignition, press and hold the button on your key, and whilst holding it, turn it to position one, and back into ignition, and the red light should stay red for a few seconds and then go out. When the red light has stopped flashing and gone out, that is when your clio should start up! "
4. Changing the coil pack. This probably will not fix the problem if the coil fault indication light is not illuminated on the instrument panel. If it is illuminated --> change the ignition coil (s). Read the OBD data first to determine the faulty coil if there are multiple.

Random notes: Lambda sensor fault should not affect the startup of a car in any way. Although it might cause bad idle once the car is running.
MAP sensor fault should not affect the starting of the car, although the car would probably hesitate to take revs when the throttle pedal is pushed.

I really laughed when I read one poster's final say on this thread:
"I know that all cars have problems, but when something wrong start to heppen with renault car, the problems becomes never ending."
Rone is offline  
For the best viewing experience please update your browser to Google Chrome