DTC 14 - P1767

Name of Code:
P-1767(14) - Relay Output Always On

When Monitored: Ignition key is turned from "off" position to "run" position and/or ignition key is turned from "crank" position to "run" position.

Set Condition: This code is set if the Transmission Control Module (TCM) senses greater than 3 volts at the Trans Relay Output (switched battery) terminal of the TCM prior to the TCM energizing the relay.

Theory of Operation: The transmission control relay is used to supply power to the solenoid pack when the transmission is in normal operating mode. When the relay is off, no power is supplied to the solenoid pack and the transmission is in "limp-in" mode. The relay output is fed back to the TCM through pins 16 and 17. It is referred to as the Trans Relay Output circuit or "switched battery".

Transmission Effects: The MIL will illuminate and the transmission system defaults to Logical limp-in mode. Logical Limp-in mode results in the same modes of operation as Relay Open Limp-in. Since the relay is stuck "on", the TCM cannot open the relay, and the TCM shifts to 2nd gear.

Possible Causes:
- Relay failure (welded contacts)
- Short to battery in 12-volt supply and/or transmission control relay output circuit(s)
- Short to voltage
- TCM connector problems
- TCM