1995 325ic cranks and cranks but no start. Yet another thread

[GTAG20]

So I received a car from my friend who had lost his key a few years ago and lost interest for the car. Ordered a new key from the dealer and filled with gas. No start. Car cranks and cranks but nothing. At first the hazard lights would go off when the battery was attached but pressed hazard button and it stopped. Not sure if the hazard button was depressed or the alarm was triggered and not allowing the car to start.

I checked fuse 18 under the hood was good and replaced it anyways. Dme relay was good and replaced it anyways. Fuel pump relay tested in switched with horn relay both confirmed working.

what should I check next

1995 obd1 no ews according to dealer. Battery is good there is fresh gas not sure what’s in the tank

[IMG]https://imagizer.imageshack.com/v2/150x100q90/922/RCjMOF.jpg[/IMG]

[drstuess]

I would Ohm the crank position sensor and see if it's in spec.

Sent from my SM-G930V using

[Eric93se]

You've read all those other threads, so you should know what to check.

[Richkid79]

Yeah...what Eric said...
I did manage to score a 94 325iC for $800 when previous owner had same problem (the black one in my sig) By the time I got it, the p/o had new fuses, relays, CPS and fuel pump installed. Still wouldn't start. I switched the DME with another red label from a 325i and fired right up. Turns out the po had used a jump box multiple times to start the car and fried the computer.

Good luck

[GTAG20]

Yea. I'm not getting the check.engine light in the dash any longer before starting the car. Changed fuel pump and relays and noticed this yesterday.

[jc43089]

Do you have a multimeter? It sounds like a good possibility is the fusible link is blown. At the jump start post check for voltage between the large wire and the small post that is somewhat hidden, the small one comes from the battery as well so you should see 0V. Do this check with the key in pos 2. If the fusible link is blown you will see some random voltage here not a hard 0 like you should. If that is the problem you can find it in the trunk, follow the red battery cables from the battery about 18" and there will be a section of heat shrink, it's under there. I got a car for 450$ because someone accidentally shorted something and blew that and didn't know how to find it. I cut the one time use fusible link out and crimped in a regular fuse holder with a 30A fuse. It's been fine for 20k miles since then.

[GTAG20]

I don't have a meter but will borrow one from my neighbour

[ed323i]

Best to buy one (multimeter).. For $10-$20 you can buy a reasonable one. These meters come in handy lots of times. With the car, but also in the house, etc.
Good to check the fusible link first. First do the test jc outlined. If that gives a troubled reading, set multimeter to low Ohms (for example 0-100 Ohm) and one pin on either end of the fusible link. Should give something below 1 Ohm (very low resistance means good connection). But you'd probably see the problem with the fusible link without testing it.

What I would test after that, if the fusible link is not the cause:
When you crank the car, does fuse 18 get any power? You can test with the multimeter. One pin on fuse 18 and one pin on ground (I often use one of the three bolts on the shock tower). Test while you let someone else crank.
If no power on fuse 18, assuming relays are good, then the DME is not working or the DME doesn't get a proper signal from the crank sensor. DME enables the fuel relay (which then puts +12V on fuse 18) with ignition on and a crank signal.
Then Ohm test the crank sensor, again using multimeter in the Ohm setting. Checking specs in Bentley manual.
If that's okay, then I'd check if the DME gets power. Check Bentley manual to see which pin should get +12V once ignition is on.
If it gets power, and ground, then it's either a dead DME or DME relay or a bad crank sensor, or bad wiring. Try to find another known-good crank sensor and another DME and swap and see what happens.

Good luck!

[XnWarden]

For what its worth, whenever ive had grounding issues or fusible links blown, or any other electrical shit, the car wouldn't crank at all.

Since yours is cranking, I'd be looking more into the mechanical side.

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[ed323i]

I think the fusible link is for the electronics, including EWS and DME, and there is a hard connection from the battery to the starter, without a fusible link in between.. So, if a car has EWS, and the electronics get no power, then it won't crank because the EWS doesn't give the 'green light'.But with a pre-EWS car, the starter can still function even with the fusible link gone.. JC, can you confirm this line of thought?

[jc43089]

XnDWrden - The car will crank all day and appear to be fine with a blown fusible link, but the CEL won't light up as a test when the key is turned on because the ECU isn't getting power.

[ed323i]

Ah, okay, interesting.. In Europe we have no CEL light, so I didn't know about this - that no CEL light after turning on ignition means that the ECU has no power (or is dead)..

So, go get that multimeter and do the tests like in JC's post (#6), and inspect the fusible link itself if needed..

Let us know how this evolves..

P.S. Perhaps it could also be the DME relay (which sits next to the fuel pump relay)? If that relay is dead, then the DME wouldn't get any power also, I'd think.. An then also no CEL light..

[GTAG20]

Thanks everyone for your replies and input . Ive taken the advice here and gone to purchase my own multimeter.

First test today is check the jumper post. Both lower terminals connect at the base One Large and one Small. My procedure if I read correctly was to ground the black lead from my meter to ground(strut tower nut) and check one lead at a time.

Both Leads show 11.78V. So both the small wire from battery to my red lead is 11.78 with the black lead grounded. Same thing with the Larger wire on the left

[ed323i]

Great work!
Fusible link is probably okay then.

What I'd do next is take out the DME relay and see if you can measure +12V on one socket pin with ignition off. And you should be able to find two pins with 12V with ignition on.
So, black wire on one of the shock tower bolts, and red wire on one of the DME relay socket pins (one at a time).

This is where you can find the DME relay:
http://www.sidonline.info/electrical/2741-2742

Update: Correction.. You should find +12V on two pins of the DME relay socket, even with ignition off.
Chart here: http://www.bimmerfest.com/forums/sho...d.php?t=823026 .

[GTAG20]

Assuming 85 socket facing firewall is ground?

- - - Updated - - -

Post was removed. So.i have no voltage anywhere with key off unless I probed incorrectly.
Key on I have voltage at 86(closest to.engine) and 30 (closest to fuel pump relay)? Hope.this makes sense

[ed323i]

Great. As long as 30 and 86 have +12V (proper 12V I assume?) then that part is okay.
Fusible links must be okay then.

Now, checking the chart I linked in my last post update, I see it's a bit more complex than I thought.

The DME always gets power at pin 26.
I assume it also gets permanent ground at some other pin.

Then, when the DME sees it fit, the DME will send a ground signal to pin 85 of the DME relay. That will 'click' the relay and the relay will send +12V to pin 87, which goes to pins 87 and 54 of the DME and to the injectors,coils,idle control valve and transmission control module.

So, with ignition on, you can test if pin 85 of the socket indeed gets ground. This you can test by setting the multimeter in the 100 Ohm setting and then connecting the black lead to one of the shock tower bolts and the red lead to the pin 85 socket pin. If it says 0-1 Ohm, then there is ground.. If it's infinite (very high) Ohms then the DME is not supplying ground (and is hence unable to activate the rest of the DME and injection system through the relay).

Update: Oh, bummer.. The chart I linked is for the M52.. And you have an M50.. So I'm not sure if it's identical.. But you can test for ground on pin 85.. Perhaps it's supplied in a different way with the M50, but it should be there with ignition on I guess.

[GTAG20]

confirmed 85 has ground key on

[drstuess]

Since you have the dmm, I would check the crank sensor.

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[ed323i]

OK.. Great.. So, the DME gets ("stage 1") power, then supplies ground to the relay (so DME also gets proper ground), which also gets 2x +12V (so no problem with fusible link). So the circuit/wires up to that point are good.
Now, what's important, is to verify if the DME relay is good. Ask someone to hold their hand on the DME relay while you turn ignition on.
You should feel and hear a click when you do so.

Also, the idle control valve should start making a buzzing sound with ignition on.

If all that doesn't happen, then you've found the source of your problem: A dead DME relay.
If it's dead, all you have to do is swap it with a known good one, and you should be ready to drive..

If the ICV does start buzzing, but the car still doesn't start, AND the check engine light doesn't turn on after turning on ignition, then it's very probable the DME itself has died.

[GTAG20]

I confirmed the DME relay is good. I was told to swap it with the horn relay and if it BEEPS when pressed its good. Also confirmed Fuel pump relay the same way. These are all 4 pin relays apparently and are the same is this correct?

Im going to look up testing the Crank sensor

I also did some searching and my car is a 1995 built January 13 1995 and has the EWS1. I read somewhere my key could be out of sync? Is this possible? I did loose the original key and key a replacement from the dealer who had it ordered from BMW in germany..... Is there a sync process i need to follow?

[GTAG20]

pulled the DME out if that helps theres still another device in that cave that sits about it. Couldnt figure out how that one comes out tho'

BjTbRw.jpg

- - - Updated - - -

this seems to be the original DME as its the correct VIN of my car

[ed323i]

If it has EWS, then it's a bit more complicated. Then you should have the codes read by someone with a laptop with INPA (and ADS) or at a BMW mechanic/dealer.. It can indicate exactly what part of the EWS process isn't working.

Does the CEL (Check Engine Light) light up when you turn on ignition?

If it does, then I think you can also check the crank position sensor.. I'm not sure if the CEL light shows or not if there is a problem with EWS.

[GTAG20]

no check engine light. I believe my car is OBD1. Does it even have that connector for a scanner to plug into it?

[GTAG20]

ok, swapped a 5 pin relay into DME relay and Check engine light is back but still cranking with no start

[ed323i]

OK.. So DME gets power now. Can you also hear the idle control valve make a buzzing sound with ignition on? If so, then the DME relay properly powers all engine electronics..

Can you verify if +12V can be measured at fuse 18 (while leaving fuse 18 connected), while cranking the engine? (multimeter in 20V DC setting, black wire to one of three bolts on shock tower, red wire on metal part of fuse 18).

If not, then, what's left is a bad crank position sensor (without RPM reading the DME won't activate fuel pump), a bad DME, or a problem with EWS, I think..