ECM trouble dtc 51 PROM error

[TheKOOK]

I recently purchased a 1988 Cheyenne K2500 4X4 and a couple of days ago the truck stalled while idling at a red light and the power seems low when accelerating. I got home and noticed the SES light came on so I checked for any codes and I got code 51 which says there an error with PROM. I removed the ECM and PROM to check for anything unusual but everything appears normal. If I were to replace the PROM which one would be the right one for my truck?

 

[Scooterwrench]

Manual or automatic?
The ECM is more than likely the 1227747 and was used from '87-'91. It could be that somone just grabbed a ECM out of the junkyard and popped it in there and it's not the right prom for your truck.
Here's a list of .bins with the broadcast codes for the 7747 ECM,

1227747 ECM Information $42

1227747 ECM Information $42 This ECM was used in 1987 to 1991 C/K Truck, Van, 4.3L, 5.7L, 5.0L & 7.4L engines. $42 Mask Click here for details on how to read error codes known as Check Engine Light (CEL) or Service Engine Soon (SES) can be found in this thread. *Work in progress*

www.gearhead-efi.com

If your truck has the correct ECM then you may be able to get the right prom for it. The ECM is behind the glovebox in the extreme right corner of the cab. You will have to pull the glovebox liner to access it.

 

[Schurkey]

MAYBE merely disconnecting the battery, removing the PROM, (using standard anti-static protocol) re-seating it, and reconnecting the battery will fix the problem.

 

[TheKOOK]

Manual or automatic?
The ECM is more than likely the 1227747 and was used from '87-'91. It could be that somone just grabbed a ECM out of the junkyard and popped it in there and it's not the right prom for your truck.
Here's a list of .bins with the broadcast codes for the 7747 ECM,

1227747 ECM Information $42

1227747 ECM Information $42 This ECM was used in 1987 to 1991 C/K Truck, Van, 4.3L, 5.7L, 5.0L & 7.4L engines. $42 Mask Click here for details on how to read error codes known as Check Engine Light (CEL) or Service Engine Soon (SES) can be found in this thread. *Work in progress*

www.gearhead-efi.com

If your truck has the correct ECM then you may be able to get the right prom for it. The ECM is behind the glovebox in the extreme right corner of the cab. You will have to pull the glovebox liner to access it.

its an automatic 5.7L

 

[TheKOOK]

MAYBE merely disconnecting the battery, removing the PROM, (using standard anti-static protocol) re-seating it, and reconnecting the battery will fix the problem.

Ill give this a shot.