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Fault Code 12 - Battery Disconnect
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Code 24 will set when the voltage returning from the TPS exceeds 4.7 volts or is less than 0.16 volts. During normal operation, the voltage range for this sensor is usually about 1.3 V with the throttle closed and between 4.0 and 4.5 volts with the throttle wide open. A fault in this that is intermitent is probably due to a loose wire or connector.

The TPS is used to control the fuel injection system, shift the automatic transmission, and control torque converter lock up. A noisy TPS, or a TPS out of adjustment may cause numerous problems without setting a fault code. See the TPS test and adjustment procedure for problems that do not set a fault code.

The TPS is located on the throttle body on the opposite side of the throttle cable. The connector should have a round rubber cover over the connections. Clear the fault codes, start the car and try jiggling the wires/connectors to try to trip a fault code. If wiggling the connector sets a fault, carefully clean the terminals of the connector and sensor, then reassemble and repeat the wiggle test.

TPS circuit tests for vehicles with a hard DTC 24.

To find the source of the code 24 problem, begin by turning off the ignition switch and disconnecting the TPS harness from the TPS. Turn the ignition switch back on. Connect a digital voltmeter across the two outer wires of the connector. The positive lead of the voltmeter should be on the violet and white wire. The negative lead should be on the black and light blue wire. The voltmeter should read 5 volts. If yes, go to 1; if no go to 2.

1.   If the TPS connector has 5 volts between the violet-white wire and the black-light blue wire (the two outside terminals), then it will be necessary to test the center wire of the circuit. It is the center wire that delivers the signal to the computer. Connect the voltmeter positive lead to the center wire (orange-dark blue) of the TPS connector and the negative lead to battery ground. The meter should read more than 2.5 but less than 4.9 volts. If it reads zero or 5 volts, disconnect the battery, remove the PCM connector, and check continuity from the TPS connector to pin 23 of the PCM connector.

2 If the TPS connector does not have 5 volts between the the two outside terminals (violet-white wire and the black-light blue wire), leave the positive lead connected and move the voltmeter negative lead to battery ground. The voltmeter should read 5 volts. If it does, go to 3; if not, go to 4.

3. If the voltmeter reads 5 volts from the TPS connector (violet and white wire) to the battery, but not to the black and light blue wire in the TPs connector, the ground circuit is bad. Disconnect the battery, remove the PCM connector, and check for continuity from the TPS connector to pin 4 on the PCM connector.

4. If no wiring problems are found, check the PCM connectors for corrosion, and reconnect. Reconnect the battery and test the circuit again. If the problem still exists, the PCM is probably bad.

This page would not have been possible without the help of Hank LaViers,
who graciously loaned me his extensive Mopar engine library



Last Update: August 8, 2001