Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 12. Using a test lamp reduces the amount of current fed into the signal circuit. The scan tool should display the maximum value for this parameter (5 volts) even though the actual voltage is higher.
2. 18. The TP 2 sensor and the APP 2 sensor share a common 5-volt reference. The 5-volt reference circuits are connected internally within the TAC module. Disconnecting the TAC module will isolate the 5-volt reference circuits.
3. 19. The TP sensor 2 and the APP sensor 2 share a common 5-volt reference. A short to voltage on the APP sensor 2, 5-volt reference circuit will affect the TP sensor 2, 5-volt reference circuit.
4. 34. When the TAC module detects a condition within the TAC system, more than one TAC system related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Disconnecting components during testing may set additional DTCs. Keep this in mind when reviewing the stored information, Capture Info.

Fig 1: DTC P1220 (1 Of 4)

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Fig 2: DTC P1220 (2 Of 4)

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Fig 3: DTC P1220 (3 Of 4)

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Fig 4: DTC P1220 (4 Of 4)

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