[alpinec1984]

Well I've just about run out of "old school" checks on my no crank/no start fault. I thought I would run it by the forums for any further checks I could make before either educating myself on running software or throwing in the towel and bringing it in. In all the ownership of the cars below I have thrown in the towel exactly twice 30 years apart - e90 water pump 500 miles from home, and 2002 alternator similarly far from home (almost made it but it started raining).

The car has always run flawlessly with 167,000mi and is totally unmolested (stock). Last week my son started it normally and drove it about 10 miles, and when he got back in to start, nothing. I went over with the rescue wagon but other key, jumps, making a second ground with a cable, etc got nothing. I roll-started the car and it ran flawlessly home, where it still did nothing on button push.

When the start button is pushed all appears normal - all accessories work, windows, lights on dash etc. There are several small whirring type noises but no big click I would associate with a stuck solenoid nor do the lights dim slightly as I would expect for that condition. Smacking the old starter did nothing. Keys work perfectly clicking in and out of slot.

Since the starter was no spring chicken I replaced it with a new Bosch unit, and also swapped the relay behind the glove box purported to fix no-start. No results exact same response.

I have checked battery, it has over 12V and I kept a good charger on it to be sure. 12V+ at jump post, the car has a new engine ground strap less than 6 months old, and engine grounding checks out good.

I read in other forums that inspecting the CAS module can reveal burned boards - is this so and does the module remove and crack open easily?

[charlie_m]

Can you scan for codes?

Try disconnecting the IBS data connector. If it starts, then replace IBS, if not then keep looking. I think there was a TSB about this

Also, the starter / alternator lead is aluminum (at least on some cars), and the strands fracture inside the crimped lug. So you can measure good voltage on the lug but there's not enough strands left to carry the starter current. Lug looks OK, but the cable will pull right out of the lug:

https://www.e90post.com/forums/showthread.php?t=1291321
https://www.1addicts.com/forums/show...php?p=21935068

[alpinec1984]

damn I searched a lot but did not see this one in time for the starter replacement yesterday, when testing/replacing the cable would have been easy. I can surely check the origination end. I did check the cleanliness of the cable connection near the jump post and verified 12V to that mounting lug but admittedly did not yank on the cable itself.

[alpinec1984]

Inspected and re-cleaned the post side of the starter cable, no change. Disconnected IBS blue connector, no change. Still reading 12.17V in engine bay, engine ground tests good (and strap is new). Getting to the other end of the starter cable not so easy.

[gbalthrop]

Originally Posted by alpinec1984

Inspected and re-cleaned the post side of the starter cable, no change. Disconnected IBS blue connector, no change. Still reading 12.17V in engine bay, engine ground tests good (and strap is new). Getting to the other end of the starter cable not so easy.

If there is NO click from the new starter when Start Button is pressed, likely the CAS Module (which acts as the Starter Relay, NOT the KL30G relay on the JB Fuse Panel ;-) is NOT activating the Starter via "Terminal 50/ KL50".

0) Does Remote Key Lock/Unlock vehicle?
1) Do you have ANY warning light on Instrument Cluster related to ELV (Electric Steering Lock), or Immobilizer?
2) Do you have any Scan Tool or Diagnostic Software (INPA/ISTA) that can read Fault Codes in CAS Module?
2a) What Fault Codes are read in CAS Module, or DME Module?
3) Do you have a Windows OS Laptop. and an hour or two to download/install INPA (BMW Standard Tools)? Only cost: $45 for BimmerGeeks K+DCAN Cable. That will allow you to read Fault Codes in ALL Modules, View Live Data in CAS Module, such as KL50 (Terminal 50) Status to see if Activation Signal is being sent by CAS Module to Starter Solenoid.

While INPA (with Forum help to get started) would make proper diagnosis easier, you can still do diagnosis of issue just with Multimeter, patch cables, and instructions based upon ISTA wiring diagrams (SSP), Line (wire) ID, Component Location & Connector View Diagrams. Those are attached to NEXT Post, so you can follow the following:

1) You can open the E-box (easier than safely getting access to Starter Solenoid), and do TWO tests:

a) Test for 12V+ at Pin #3 of Connector X6011 (X6011/3), Black wire labeled "S_50" in CAS SSP/ wiring diagram. If NO 12V+ in reference to chassis ground when START button is pressed with foot on clutch, then see checklist below.

b) If there IS 12V+ at X6011/3 when START pressed with foot on clutch, test wiring from that point to Starter Solenoid as follows:
i) Make SURE that Gearshift is in NEUTRAL and Parking Brake fully set, as Safety Switches are disabled when doing this;
ii) with Black wire from CAS disconnected so as NOT to damage CAS, apply 12V+ "Jumper" to Starter Solenoid side of X6011/3 wiring (wire going to X60531/X60551. If wiring is OK, that should "Jumpstart" the Starter and Starter should crank engine.

It is highly likely that you have NO voltage at X6011/3 when START button pressed, but "hotwiring" starter DOES cause cranking. In that case, you COULD have issue with one of following:
1) Clutch Switch NOT sending signal to CAS that Clutch is Pressed;
2) Bad Load fuse to CAS Module, F51;
3) ELV issue;
4) Immobilizer issue;
5) KL50 wiring issue;
6) "Other" (UNKNOWN Gremlin ;-)

Please let us know what you find,
George

[gbalthrop]

Attached are ISTA ScreenPrints for 2006 330i MT, showing CAS wiring diagram related to Starter (M6510a) Activation (KL50),
Component ID, Line (wire) ID, Component Location & X6011 Connector View. Please let me know if further info needed.
George

[alpinec1984]

I think I will bite the Whole Bullet and install INPA and order a cable. With one modern BMW in the family becoming three inside of 3 months, it is inevitable.

That said in the interim I will answer the questions above

0. Yes both keys lock and unlock. Everything except the starter that normally works with an unstarted car works with either key and normal pre-start dash light light up
1. No ELV or immobilizer lights, steering wheel unlocks and steers
2. Do not have a scan tool but working on it

What is the easiest way to jump the clutch press signal (temporarily only of course)? That seems easy to do to eliminate that possibility.

[alpinec1984]

F51 tests GOOD which makes sense considering how many things work. Glove box light restored and whirring noises when fuse put back in.

[alpinec1984]

OK I opened the E-box and tested by meter as directed:

I DO have 12V at X6011/3 for several seconds to test probe inserted from top (well, 11.57 versus 11.9 at jump terminal) when start button is pushed with clutch depressed of course. I hear more click(s) than I thought I would from the engine bay but no action from the starter definitely no spin or solenoid movement that I can discern.

I don't quite get why I would now apply 12V jumped to the same terminal X6011/3 when we just had 12V there or close? Isn't that the same thing? And which side of that X6011 plug is the supply side and which goes to the starter?

Yes I need to put the charger back on.

Is inadvertent yanking of the starter wires during gasket service of the pan, valve cover, and oil pressure a plausible way to cause this? That was done only a few months ago, but the car started flawlessly 50 times since.

[alpinec1984]

Problem Found!!! I looked down through the slot between the intake manifold runners and I can see that the spring-clipped plug head on the starter motor is not in place. I did the "short cut" of pushing the manifold to one side, and my guess is the bottom of the manifold pushed in the clip and pushed off the plughead, which was not very hard to remove in the first place. This would be a good place for one of BMW's impossible-to-remove clips they so dearly love.

I am going to try to retrieve the wire and get it plugged in through the little slot, rather than removing the manifold again. I do not have doll hands unfortunately.

[alpinec1984]

If anyone knows where the plugheaded wire on the starter goes that would be very helpful. I am trying to retrieve it from the top but I can't even see it, and my coat hanger fishing expedition caught nothing.

[alpinec1984]

Car is alive and well!

I had to pull the manifold back off to make sure I could clip the starter lead correctly. I am surmising that the dielectric grease I use on all connection boots made the plughead slide off real nice while fitting the manifold. The manifold is only about 1/2" away from the "push" clip part of this plughead so I advise all starter motor swappers to check with a flashlight that the wire remains in place after getting the manifold back into position.

Props to George for laying out the way to diagnose the issue. Once focused on the starter wiring only it was cake.

[alpinec1984]

This car is quite simply the BALLS. That is all.