FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

P0068

Test 1 - Test 4:




Test 5 - Test 8:




Test 9 - Test 12:




Test 13 - Test 16:




Test 17:






SYMPTOM
P0068-MANIFOLD PRESSURE/THROTTLE POSITION CORRELATION

WHEN MONITORED
With the engine running and no MAP Sensor or TP Sensor DTC's set.

SET CONDITION
The PCM determines a valid range in which the TP Sensor should be, at a given RPM/Load. The actual TP Sensor voltage is then compared to this value. If the TP Sensor voltage does not fall within the expected range within a predetermined time an error will be detected. Two Trip Fault.

POSSIBLE CAUSES
- Good trip equal to zero
- High resistance in MAP (K6) 5 volt supply circuit
- Resistance to ground in MAP (K6) 5 volt supply circuit
- MAP sensor
- High resistance in (K1) MAP signal circuit
- Resistance to ground in (K1) MAP signal circuit
- High resistance in (K4) MAP ground circuit
- PCM
- TP sensor operation
- High resistance in TP sensor (K6) 5 volt supply circuit
- Resistance to ground in TP sensor (K6) 5 volt supply circuit
- TP sensor
- High resistance in (K22) TP signal circuit
- Resistance to ground in (K22) TP sensor signal circuit
- High resistance in TP (K4) sensor ground circuit
- PCM