08 Thomas 6.7 cummins won't start or crank

[Ammogan]

The battery is good and fully charged, starter was tested and the bendix is engaging. All the fuses are good and relays are good? (Not sure that Im reading them correctly). Voltage is 12.6 at + batt term and ground so no ground short. It is in fact in neutral and emergency exits are closed. Bus has been sitting for one month with me starting it every week (but this week) when I went to start it, it acts like a bad starter no crank/turn over no start. There is a code ecu 128 when I turn the key. What can I check next? Any ideas will be helpful thanks.

[Simplicity]

What is a code 128??

If your interlock system is active, that would cause your issue.

While the gear selector may say it's in N, and in fact it may, but your neutral safety switch may be stuck open.

You can try jumping the start or crank relays to see if it turns over, maybe even starts. If you do this, block the tires and really make sure it's in N.

[Ammogan]

Thank you for your reply! It ended up being a blown relay that was hidden behind the relay panel. ��

[Simplicity]

My first No crank was the lead on a diode the size of a cooked grain of rice. Each diode lead was in a plastic tube, then it was wrapped up with the connector the diode was attached to tucked in the far back of a rat nest of wires in my rear panel. How we got so lucky to find it, I don't know!

The second no crank was the same symptoms, yet this time the start relay, or so we thought. It happened two days before my first trip...worked fine all the way until two hours away from home.

I started a thread about the ordeal if you care to read it. Just search under "broke down in Yakima".

Glad it's working!