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P0128 Diagnostic Trouble Code Discussion for June 2007

Thermostat System Malfunction


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Trouble Ticket Help Requests for DTC P0128
Help Request Posted
2005 Jeep Grand Cherokee Laredo 3.7L MIL Lamp on VIN: 1J4GR48K65
P0128: Thermostat Rationality. scan freeze frame and found code po128 set after engine ran 641, i beleive this is IN seconds so about (10 minutes), it was running at 1336 rpm at 68 mph ambient temp was c 22 degrees , intake air temp was c 21 degrees and the coolant temp was c 49 degrees whi...
June 26, 2007
2005 Jeep Grand Cherokee Laredo 3.7L MIL Lamp on VIN: 1J4GR48K65
P0128: Thermostat Rationality. scan freeze frame and found code po128 set after engine ran 641, i beleive this is IN seconds so about (10 minutes), it was running at 1336 rpm at 68 mph ambient temp was c 22 degrees , intake air temp was c 21 degrees and the coolant temp was c 49 degrees whi...
June 26, 2007