DTC P1121: Throttle Position (TP) Sensor Signal Lower Than Expected: General Description
The throttle position (TP) sensor detects the position of the throttle valve. When the throttle valve is open (low-vacuum), the manifold absolute pressure (MAP) sensor outputs a high MAP value, and when the throttle valve is closed (high-vacuum), it outputs a low MAP value.
If the TP sensor detects a throttle position that is less than the set value when the MAP sensor outputs a higher MAP value (higher pressure) than the set value, a malfunction is detected and a DTC is stored.
MONITOR DESCRIPTION CHART
| Execution | Under the Enable Conditions |
| Sequence | None |
| Duration | 2 seconds or more |
| DTC Type | Two drive cycles, MIL ON |
ENABLE CONDITIONS CHART
| Condition | Minimum | Maximum | ||||
|---|---|---|---|---|---|---|
| Engine coolant temperature | 158°F (70°C) | - | ||||
| Engine speed | 1,300 rpm | 5,500 rpm | ||||
| Vehicle speed | 15 mph (24 km/h) | - | ||||
| MAP value | 83 kPa (620 mmHg, 24.5 in.Hg)(1) | - | ||||
| 50 kPa (368 mmHg, 14.5 in.Hg)(2) | ||||||
| No active DTCs | MAP, ECT, TP, EGR, BARO, IAC, Fuel System, Misfire, Intake Air System | |||||
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