P1633!!!!!

[JDSTROKER]

Cant get rid of this code. Cycle power heck wngine light is off for approximatly a minute And then it comes on. Got new batteries. Good grounds. Ive hecked fuses. What else could this be?

[f250Jason]

From the service manual
"P1633 TCM indicates keep
alive power circuit
has experienced a
voltage interrupt

An intermittent or open in the
keep alive power circuit.
TCM freezes shift adapts.
Malfunction Indicator Lamp
(MIL) is illuminated.

For diesel engine vehicles, CLEAR the
DTC from continuous
memory and rerun the self
test. If the DTC returns, GO
to Pinpoint Test K.
"

Attached is pinpoint Test K....run through that and you should have your answer.

[JDSTROKER]

Ran through the test. Wants me to go to section 414-00. I stop at step k3 about checking charging. My check engine lamp stays on. Where did you get this info?

[f250Jason]

It is the Ford Service Manual. If you search for 'Service Manual' in the 6.4 section, a user has posted it. I'll find your next step and post it for you.

**EDIT** You'll be best downloading it yourself. That is a large section focusing on the altenator. Possibly a charging issue?

[JDSTROKER]

Ok i went through te wiring schematic and found that pin 46 on chassis controller is kapwr. Checked it with key off an its battery voltage. Key on engine running its battery voltage. Bad pcm?