Double post

 

This is very helpful !

So now the focus is on the starter relay....questions to answer when no-crank/start happens :

- is starter relay pin 1 getting 12v ?

if yes, then relay isn’t closing or contacts are dirty and 12v not passing thru to solenoid

if no, then check the shifter position sensor, starter diode, ignition switch.

Great, now I have a program , I’ll report back.

Thanks again.

 

Just to be clear. This is from my 2011 EVTM. The starter relay closes with the key turn etc. BUT, it's contact's feed 12 volts via Fuse13 to the solenoid at the starter. Two separate sources.

 

I have two hard wired test lights in place:
1) - at the small terminal on the solenoid
​​​ 2) - at terminal 85​​ on starter relay, this is the electro magnet side of the relay, it shows that the relay is being activated and when it pulls the relay contact switch closed, if all works as it should then 12v would be at 1).

Yesterday , the no-crank/start happened and
light 1) was off but
light 2) was on

I knocked on and wiggled the starter relay but van wouldn’t crank/start. Last time I had exchanged the starter relay with another in the BJB so maybe the relay is working but I’m not 100% sure. I can hear something click when the key is turned. I also have to check if terminal 30 on the starter relay is hot , need one more light between pin 30 in starter relay and ground. I feel like I’m building a diagnostic scanner!!

Or I could buy a new relay but I hate to approach problems by throwing parts at it.

On my wiring diagram terminal 30 goes to Power Distribution.

-Onward

 

You are getting close! you need that 12volts into the relay contacts (term30). maybe next time take a 12 v jumper and touch a few spots to see if you can get it to crank.

 

I have to admit in front of all of you that I’ve missed picking up on some important clues to this whole thing which have been mentioned along the way and might be the root cause to the intermittent no-crank. This clue is the red anti-theft light, I just noticed that when the van won’t start , that red light is blinking but when it does start , the red anti-theft light is solidly on and not blinking. This has got to be an important clue.

Normal starting:
red anti-theft lite is solid on
Starter relay pin 30: 12v always
Starter relay pin 86: 12v only when key turned
Jumper wire from starter relay pin 30 to 87:
engine cranks and starts normally.

No-crank/no-start:
red anti-theft lite is BLINKING
Starter relay pin 30: 12v always
Starter relay pin 86: NO VOLTAGE when key
turned, no cranking/starting
Jumper wire from starter relay pin 30 to 87:
engine cranks but won’t start.

To me , it appears that the anti-theft mechanism is occasionally being activated and when it is, voltage is shut off from various important components like the starter relay and maybe the fuel pump , ignition module etc.

Your thoughts? (besides what a knucklehead this guy is . )

Thanks.

 

Some help , maybe.
Are there any aftermarket devices on your vehicle ? Remote starter,alarms, even something like a brass key tag can mess with the transponder.

PATS= passive anti-theft system

Vehicle Disablement
PATS will disable a vehicle under the following conditions;
Damaged encoded PATS key
Unprogrammed key
NON-encoded key (key has no electronics)
Wiring problem to PATS Control or transciever
Transceiver concern
Communication network concern
PATS Control module concern
PCM concern

A while back , I believe we mentioned a possible problem with the keys. Not fully knowing exactly what you have , see if any of the Disablement conditions apply.

When the PATS is activated to prevent starting it will disable the ground to the starter relay, and disable the fuel pump AND injectors.

 

I’d have to say that these items from the list apply:

-Unprogrammed key
-NON-encoded key (key has no electronics)

I just have a flat metal key and a key with a small plastic covering, but both works most of the time however definitely not always.

 

What I don’t understand is why using the same keys, the anti-theft system is triggered only some of the time but not all of the time.

is there a way to disable this like cutting a wire from the ignition switch or is the only solution to go and get a programmed key from the dealer?

 

To the best of my knowledge there is no shortcut .
The dealership may be able to program a key or two , but you will need to bring proof of your owning the vehicle.
They will need to access your vehicle's info in it's computer from the mfg website and program keys from there for your particular vehicle..
Until you get that done, you could be spending a lot of $$$ for things that will not work.
You could also have a certified locksmith (has access to the security info on the mfg website) and he/she could come to your home and program keys. Locksmith might be somewhat less expensive, best to get estimates..