start but no run

[babycritter]

i have a start but won't stay running. no check engine light or theft light with key turned on bulbs are good. code is U1451. got it from grandson who knows nothing about it. he had a amp hooked up to battery for stereo. it fried something. it's a 1997 expedition 5.4 xlt

 

[Bedrck47]

U1451
Theft Module Signal Engine Disabled

U1147 Vehicle Security Status Message Missing

• Circuitry.
• Multiplex communications network concern.

GO to Pinpoint Test A .


A1 CHECK THE THEFT INDICATOR OPERATION

Check the THEFT indicator operation.

• Does the THEFT indicator illuminate for 2 seconds, flash continuously for 1 minute, then flash the code sequence 16?

YES
GO to A2 .

NO
System is OK.
A2 CHECK VEHICLE STATUS

Verify the starting of the vehicle.

• Does the vehicle start?

YES
REFER to Section 3A in the Powertrain Control/Emissions Diagnosis Manual for diagnosis and testing of the powertrain control module (PCM) (12A650) (PCM).

NO
REFER to Section 418-00 .

 

[docraymund]

What you could try to do is this: disconnect all unnecessary sensors for the engine to run. Just keep the MAF, TPS, crank and cam sensors, coolant temp sensor connected. If the engine runs, connect the remaining sensors one by one. to determine which is faulty.But before you do this, try a soft reset first.

 

[stamp11127]

None of the engine sensors will throw a theft code. Until the code is cleared and the cause of it corrected, you aren't going anywhere since the pcm thinks a theft is occurring.

Make sure you clear the code and see if it returns when trying to start.

 

[babycritter]

Like i said the check engine light and theft light do not light up when i turn the key on. I cleared the codes but they come right back. the ground wire from back of block to firewall is all red like it got real hot. Is there a reset button on the pats control module? For the bedrck 47 i couldn't get any of the things you posted.

 

[Bedrck47]

Send me a Private message with your e-mail I will send you what I posted

 

[babycritter]

How

 

[babycritter]

Got that fixed it sounds good. But windshield wipers won't work.

 

[stamp11127]

And the solution to your problem was.........

 

[babycritter]

the theft system was unplugged stupid me like i said is that i just got it when i started working on it. just one more issue is windshield wipers front and back but will get it when it warms-up outside