If you don't have a manual,Possible causes:
-- CMP circuit open.
-- CMP circuit shorted to GND.
-- CMP circuit shorted to PWR.
-- SIG RTN or CMP/TSS GND open (VR type).
-- VPWR open (Hall effect type).
-- CMP Sensor (Hall effect type) not installe correctly.
-- Damaged CMP Sensor.
-- Damaged PCM.
If engine will start
l Complete PCM Reset to clear DTCs.
l Start engine.
l Increase rpm to greater than 1500 rpm for 10 seconds. Repeat two times.
l Key off.
l Retrieve all Continuous Memory DTCs.
l Is DTC P0340 present?
Yes
For VR type CMP:
GO to «DR5».
For Hall Effect type CMP:
GO to «DR3».
Not sure which type or how to ID which type????
DR5
DR5 CHECK FOR OPEN CMP AND SIG RTN CIRCUITS BETWEEN PCM AND CMP SENSOR
l Install breakout box, leave PCM disconnected.
l Measure resistance of CMP circuit between PCM test pin 85 and CMP sensor harness connector.
For VR type CMP (Contour/Mystique, Escort/Tracer):
-- Measure resistance of CMP/TSS GND circuit between PCM test pin 76 and CMP sensor harness connector.
l For VR type CMP: (All others:)
-- Measure resistance of SIG RTN circuit between PCM test pin 91 and CMP sensor harness connector.
l Are resistance measurements less than 5.0 ohms?
Yes
GO to «DR6»
DR6 CHECK CMP CIRCUIT FOR SHORT TO POWER IN HARNESS
l CMP sensor disconnected.
l Key on, engine off.
l Measure voltage between PCM test pin 85 and PCM test pins 51 and 103.
l Key off.
l Was voltage less than 1.0 volt?
Yes
GO to «DR7».
DR7 CHECK CMP CIRCUIT FOR SHORT TO GND AND SIG RTN IN HARNESS
l CMP sensor disconnected.
l Disconnect scan tool from DLC.
l Measure resistance between PCM test pin 85 and PCM test pins 51, 91 and 103.
l Was each resistance greater than 10,000 ohms?
Yes
GO to «DR8».
This just keeps on going and going and going.
this is from Ford CD manual. Well part of it.
Personally I've never had this trouble, but from Demon said, I wouldn't mess around to long and get it to the dealer before it damages something.
Paul
