Car won’t start - battery fine.

[MitchT]

Went to give my E36 3 Series a run this morning, for the first time in about a month, but it wouldn’t turn over when I turned the key. I’m pretty sure the battery is fine as it’s on a CTEK MXS5.0, the central locking wasn’t sluggish and the usual dashboard lights illuminated when I turned the key. There was nothing else though. No starter motor noise - nothing! Any ideas?

[MitchT]

Cheers for the replies. I’ve been out for the morning but will investigate after I’ve had my lunch.

[MitchT]

98elise said:

Give the starter motor a whack. Use a long piece of wood and a hammer.

I've had a long, hard look under the bonnet and I can't for the life of me work out where the starter motor is! I've Googled for pics but nothing that's visible looks like it.

ian332isport said:

Could be the EWS immobiliser.

When you turn the ignition on, the EWS will read the transponder inside the key. If it’s not happy for any reason, it won’t crank. There’s a relay inside the EWS module that you can hear click when everything is good. It should click within a second or so of turning the ignition on, and will click back out again about ten seconds after you turn it off.

It’s hidden up behind the glovebox, but you can probably hear it if you get close enough. Maybe open the glovebox too. Failing that, it’s not hard to remove the glovebox.

If you can hear it click, it’s not the immobiliser.

I'm not sure about a click but I can hear a buzzing noise when I turn the key. It stops a few seconds after turning the ignition off.

[MitchT]

cuprabob said:

That's probably the fuel pump priming.

There's a different noise which I thought was the fuel pump priming. This is very much an electrical buzzing noise.

[MitchT]

MB140 said:

Take a jump lead...

GreenV8S said:

A voltmeter...

Unfortunately the extent of my car maintenance knowledge is keeping on top of fluids, tyre pressures, bulbs, etc. I don't possess any of these items!

ian332isport said:

When you turn the ignition on, or try to start?

When I turn the key to the first position. That said, it's not doing the buzzing noise now, just the usual sounds that it makes.

ian332isport said:

Out of interest, what year/model are we looking at?

1999 318is with 1.9 M44 engine.

I think I finally found the starter - it's tucked well out of the way in the dark recesses of the engine bay. I've given it a tap with a hammer via a long screwdriver, but it hasn't made a difference. Maybe I wasn't tapping hard enough.

I suspect I'm going to have to call a guy from a garage down the road, see if he''ll bob round and take a look.

[MitchT]

Saleen836 said:

Stick the car in gear and rock the car,if the starter is stuck this can also free it up

Just tried that. Still nothing.

ian332isport said:

Just to clarify. First position is accessories, second position is ignition on and third position is cranking. You will only hear the click when you go to the second position.

You really do need to confirm the EWS module is clicking (single click for on. second single click for off). If this doesn't click, it will never try to crank and you have an immobiliser problem.

Just tried this. When I turn the key to the second position there is a muffled kind of click and an electrical hum starts like the car's electrical systems have woken up. After turning the key back again the electrical hum goes on for a few seconds with the same muffled click happening when it stops.

[MitchT]

ian332isport said:

I’m not convinced you’re hearing the EWS relay clicking. There’s loads of things that power up when you turn the ignition on. There should be a good ten second delay before the EWS relay clicks back out when the ignition goes off.

Your best bet is to remove the glovebox and locate the EWS module. It’s a very obvious click when you’re close to it. You may even feel it if you have it in your hand. The EWS module is about the size of a packet of cigarettes and has one large connector on the end. It will say EWS on it, so easy to identify.

Something clicks behind the glovebox 7 seconds after turning the key from position 2 to position 1. It's quite a dull and muted click though. I can't say I've ever heard a particularly noticeable click in the past - the noises I hear now are the same as I've ever heard.

As an aside, though, if it is the EWS that's at fault, what's the solution? New one I guess, but will it need to be paired with the key?

On the subject of the key - I'm using the second key as the casing on the main one broke apart some years ago when I was using it to unlock the car and the lock was very stiff. I've been meaning to replace it since but not got round to it as it's a main dealer job and there isn't one near me.

phumy said:

To be sure its not the battery, get it out and charge it over night. Then reconnect and try starting again

I had a ctek on my Aston since last September, went to start it 2 weeks ago, battery was flat as a pancake. I bought a new battery as the old one was 7 years old, once fitted she fired up instantly.

Charge it up properly with a proper charger.

I don't have access to a proper charger, but it's worth mentioning that I had the sills done and some fuel lines replaced in January. During that process the battery was disconnected and needed recharging. After I got the car home and it had sat for a few days the battery was flat again. The CTEK recharged it perfectly well at that point. Also, as the central locking, windows, radio, fan and dashboard lights are all behaving normally I'm not convinced it's the battery. When my last battery was dying the central locking and windows were sluggish for a while before it reached the point that the engine refused to fire up. The current battery will be five years old at the end of October but, in the past, they've always lasted nine years.

[MitchT]

Just to add...

I'll be passing Halford's tomorrow so I'll buy a Multimeter so I can check the battery, just in case.

The current battery is a "Bosch S4 Car Battery 075". It cost me £69.99 from Euro Car Parts. I've just been on their website to check and the same unit is now £148.99! WTF is that about?

[MitchT]

paintman said:

Some batteries you're doing well if you get to the end of their warranty period!

I've always had nine years out of my batteries, hence my difficulty in accepting it might be this.

phumy said:

My money is on the battery being fked.

Could be right. I'll go and get that multimeter after work, then I'll know.

My difficulty in believing that it's the battery, thus far, is down to the fact that, previously, when a battery has been flat, the central locking was sluggish or didn't work at all, electric windows were slow and when I tried to start the car the dashboard would light up like a nightclub. These things are behaving perfectly normally this time! Anyway, we'll know this evening!

[MitchT]

cuprabob said:

ECP prices are generated by a random number generator

Tayna Batteries are good
https://www.tayna.co.uk/car-batteries/bosch/s4004/

Cheers - if it is the battery I'll order that!

[MitchT]

I've owned the car from three months old. It was new in May 1999.
First battery - BMW branded - lasted nine years.
Second battery - Bosch Silver installed by a mechanic - lasted nine years.
Third battery - the current one - Bosch S4 installed by me in late October 2016.

As an aside, when I get the multimeter on the battery later, does the key need to be in the ignition and, if so, in which position? The stuff I've read online suggests I should turn the headlights on for 30 seconds to get rid of any residual charge that might be lurking on an otherwise flat battery, before testing it, but it doesn't say whether to remove the key from the ignition after doing this before testing the battery.

[MitchT]

What are the YouTube videos I've seen showing then? They appear to be testing the voltage of the battery to determine if it needs replacing or not.

[MitchT]

The Haynes website says what I've already seen elsewhere; Connect a multimeter to the battery terminals and look for 12.6V or more. 12.2V means only half charged and 12V means effectively discharged.

Anyway, I've disconnected to CTEK so we'll see later if the central locking, windows, radio, etc. have degenerated from normal to flat battery behaviour. If so then I'll buy a new battery.

[MitchT]

Having disconnected the CTEK at lunchtime I’ve just tested the battery with a multimeter - rightly or wrongly, given the conflicting advice in this thread. Anyway, it read 12.75V which seems OK. I’ll try again tomorrow evening when it’s had more of a chance to drain but, for now, I’m increasingly of the belief that it’s not a battery issue.

[MitchT]

ian332isport said:

Next step is to check for 12v on X20 pin 18 while cranking.

When you say “while cranking”, do you mean while the key is turned fully clockwise? I ask as no actual cranking happens. When the key is fully turned clockwise and the starter motor should operate, nothing happens at all.

[MitchT]

Thanks both - I'll try to take a look at lunch time. Failing that, after work.

[MitchT]

Just had another quick go with the mutimeter...

Today's readings:

12.66V - no key.
12.65V - key in position 1.
12.48V - key in position 2.
12.47V - key in cranking position.

I don't know if any of that reveals anything useful to anyone more knowledgeable than myself.

I'll investigate the "X20 pin 18" and battery cable possibilities after work.

Edited to add...

At risk of sounding stupid, can someone explain what is meant by "X20 pin 18"?

Edited by MitchT on Wednesday 16th June 14:25

[MitchT]

First:
Checked the fuses. All look OK.

Second:

ian332isport said:

I mentioned it in one of my previous posts. Most BMW connectors have an X number for identification purposes on the wiring diagrams. X20 is the designation for the big 25 pin connector next to the fuse box. This connector is the main connection between the body wiring harness and the engine wiring harness.

There's actually a couple of similar connectors next to each other, but the X20 is the one nearest the strut tower. The one at the back is the X69 connector.

If you pull the rubber boot back, you can access the wires inside. You may need to unclip it from its mounting to get the boot off. You'll find a small screwdriver helps to hook the boot back.

Once inside, you want to find the wire on pin 18. They are numbered on the plastic housing, but it's not easy to see. Just look for a reasonably fat wire that's yellow with a thin black stripe. This wire absolutely must go to 12v when you try to start the car. This is the signal that tells the starter solenoid to activate. It's basically the other end of the wire that comes from the ignition switch, although it passes through the EWS relay on the way.

Mine seems to be at the opposite side from the fuse box. I'm guessing it's this...



Amazingly, I can read the tiny numbers next to the holes. The question still remains... if I manage to expose the pin 18 wire, how do I test it? If I'm using the multimeter, which probe goes on the wire and where does the other probe go?

[MitchT]

I'm stumped then. Is anything that's visible in this photo the X20?

[MitchT]

ian332isport said:

Can you do a general picture of the engine bay?

I'll get one at lunch time.

ian332isport said:

I’m struggling to find a good RHD 318is engine bay picture online. What I have found doesn’t show the X20. I think it may be tucked up on the bulkhead behind the battery though.

I suspect it's hidden behind/underneath the battery. When I search online for "X20" pics I just get images of the diagnostic port, hence why I wrongly though that was it earlier.

shakindog said:

Always Start with the basics...

Battery - checked.
Starter - given it a wallop.
Fuses - checked.
Wiring - looks alright, though I'm no expert.
Volt drop earths - lost me with that term!

I have breakdown but not homestart. I'm pretty sure a guy at a small garage down the road will come and have a look but I don't want to bother him unless I run out of options. Want to get on top of this X20 thing first, then I'll give him a shout.

Thing is, the car was fine when I last parked it in the garage. The problem has arisen entirely on its own!