Test A: No Communication With Rap Module
- Turn ignition off. Check fuses No. 4 (5-amp) and No. 8 (5-amp) in instrument panel fuse block. If fuses are okay, go to next step. If fuse(s) are blown, replace fuse(s). Retest system. If fuse fails again, check for short to ground in appropriate fuse circuit.
- Turn ignition off. Disconnect RAP module 22-pin connector C257. Turn ignition on. Measure voltage between ground and C257 connector terminal No. 12 (Orange/Light Green wire). See Fig 1
. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, repair short in Orange/Light Green wire. Retest system.
Courtesy of FORD MOTOR CO.
- Turn ignition off. Disconnect RAP module 26-pin connector C256. Turn ignition on. Measure voltage between ground and RAP module 26-pin connector C256 terminal No. 25 (Black/Pink wire). If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, repair Black/Pink wire Retest system.
- Turn ignition off. Measure resistance between ground and RAP module 22-pin connector C257 terminal No. 14 (Black/Light Blue wire). If resistance is less than 5 ohms, see MODULE COMMUNICATIONS NETWORK article. If resistance is more than 5 ohms, repair Black/Light Blue wire. Retest system.