2002 Pontiac Grand Prix

2002 Pontiac Grand Prix 6 cyl Front Wheel Drive Automatic 125000 miles

Cruise quit working one day. Checked the fuse and it was ok. Took it to the shop and was told I need a new cruise control module. First off, where is this module located and secondly, can a wannabe shade tree mechanic handle replacing this? They wanted $359 for the module and another $100 to install. Please help.
June 19, 2009.

CRUISE CONTROL INOPERATIVE/MALFUNCTIONING Diagnostic Aids Conditions for Enabling Cruise Control  When vehicle speed is more than 40 km/h (25 mph)  When PARK, REVERSE, NEUTRAL, or 1st gear is not indicated.  When an over/undercharged battery condition does not exist.  With normal engine RPM. IMPORTANT: Perform the following in order to avoid misdiagnosis.  Inspect for proper operation of brake lamps.  Inspect throttle linkage for mechanical binding which could cause the system to malfunction.  Inspect cruise control cable adjustment, should have minimum slack.  Inspect for stored Diagnostic Trouble Codes (DTCs) in the PCM.  EMI on the speed sensor signal circuit may cause erratic cruise control operation. Module is 2nd diagram with part 2 pointing to it.

Jun 20, 2009.