Nissan Altima Forum banner
1 - 2 of 2 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
I'm going to detail the problem and few solutions steps I've taken with no luck.

The vehicle was working normal, parked to go into a restaurant and when came out it wouldn't start.
1. I had it towed to the home, tried checking the brake switch, brake light works, dashboard shows as if breaks are engaged before starting.
2. Changed key fob batteries, no luck...
3. Display panel (Dashboard) all lights up, but nothing happens when pushing the start button.
4. I wanted to see if it was the battery and got a new one, replaced with a new one and no luck...
5. I thought it may be the starter relay (from a forum suggestion), I tested the starter by using a wire from the positive battery pole to the the starter relay area and the starter turned over (I'm thinking that it can't be the starter if it tried to start) so I bought a new starter relay, still no luck...
6. I have a diagnostic tool in the mail, will try and get a code from this.

I'm out of ideas now, not sure what to do, any suggestions? Thank you!
 

·
Registered
Joined
·
465 Posts
There's an awful lot of things that can cause a no-crank on an I-key car, so start by eliminating the obvious. If there's a solid red security light on the dashboard then you have a key issue that may have put the ECM in Lock Mode. If so you can try putting the key in the doghouse and let the IMMU read it instead of the BCM. That uses an RFID system completely separate from the "broadcast" I-key signals. If there are no security issues, is the car showing Park in the cluster? If not, the TCM or Range Switch may have an issue. If it shows P, put a test light on pin 80 of the IPDM, a fat B/Y wire. Here's the IPDM terminal layout:

10965


Pin 80 should go hot when the car tries to crank, if it does then you have an open wire or high resistance between the IPDM and the starter solenoid. If it doesn't, then check to make sure the IPDM has main power on pin 2. If it doesn't, there are two fusible links upstream from it, Link E 100A in the battery card and Link L 40A in the fuse and relay box. If main power is good then there are two relays built into the IPDM, Starter (ST) and Starter Control (SC), one of them is blocking juice to the solenoid. To find out which, put a voltmeter (not a test light) on pins 72 and 46 while trying to crank. Pin 76 comes from the TCM and should go to 12V, pin 46 comes from the BCM and should go to near 0V. If 72 doesn't go hot then there's probably a Range Switch issue, it 46 doesn't go to ground then the BCM may have a blown driver or other issue. If they both behave properly then your IPDM is bad.
 
1 - 2 of 2 Posts
Top