sounds like 1765 is your root cause. you need to perform some diag on that code. there are several possible causes. your best bet, because you probably do not have the equipment to diagnosis it properly is to take it to your local dealer.
Theory of Operation
The Transmission Control Relay supplies power to the TCC, Overdrive, and Governor Pressure Solenoids when in normal operating mode. The Transmission Control Relay Control circuit is constantly monitored by the PCM. If the expected state of the Transmission Control Relay Control circuit is different then the expected state, a corresponding DTC will set and the PCM will de-energize the Transmission Control Relay and place the transmission in Limp-in.
When Monitored:
Continuously with the Ignition on.
Set Condition:
This DTC will set if the PCM monitored voltage of the Transmission Control Relay Control circuit is different than the expected voltage for the period 3.0 seconds.
Possible Causes
FUSED B(+) CIRCUIT OPEN
(T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT OPEN
(K125) GENERATOR SOURCE CIRCUIT OPEN
(T515) TRANSMISSION CONTROL RELAY CONTROL SHORT TO VOLTAGE
(T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT SHORT TO GROUND
(T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT SHORT TO ANOTHER CIRCUIT
TRANSMISSION CONTROL RELAY
POWERTRAIN CONTROL MODULE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
1. CHECK IF THE DTC IS CURRENT
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Ignition on, engine not running.
With the scan tool, read Engine DTCs.
Record the Freeze Frame data for the reported DTC.
With the scan tool, erase DTCs.
Turn the ignition off to the lock position.
Using the Freeze Frame data recorded earlier, try to duplicate the conditions in which the DTC originally set.
NOTE: It may be necessary to road test the vehicle to duplicate the original set conditions.
With the scan tool, read Engine DTCs.
Did the DTC reset?
Yes
Go To 2
No
Go To 11
2. TRANSMISSION CONTROL RELAY NOT CLICKING
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With the scan tool, actuate the Transmission Control Relay.
Is the Transmission Control Relay clicking?
Yes
Go To 11
No
Go To 3
3. CHECK THE TRANSMISSION CONTROL RELAY
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Turn the ignition off to the lock position.
Remove the Transmission Control Relay.
NOTE: Check connectors - Clean/repair as necessary.
Install a substitute relay in place of the Transmission Control Relay.
Ignition on, engine not running.
With the scan tool, erase DTCs.
Start the engine.
With the scan tool, read Engine DTCs.
Does the scan tool display the DTC P1765?
Yes
Go To 4
No
Replace the Transmission Control Relay.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
4. CHECK THE FUSED B(+) CIRCUIT FOR AN OPEN
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Turn the ignition off to the lock position.
Remove the Transmission Control Relay.
Ignition on, engine not running.
Using a 12-volt test light connected to ground, check the Fused B(+) circuit in the Transmission Control Relay connector.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
Go To 5
No
Repair the Fused B(+) circuit for an open. If the fuse is open, make sure to check for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
5. CHECK THE (K125) GENERATOR SOURCE CIRCUIT FOR AN OPEN
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Using a 12-volt test light connected to ground, check the (K125) Generator Source circuit in the Transmission Control Relay connector.
Does the test light illuminate brightly?
Yes
Go To 6
No
Repair the (K125) Generator Source circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
6. CHECK THE (T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
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Turn the ignition off to the lock position.
Disconnect the PCM C2 harness connector.
Ignition on, engine not running.
Measure the voltage of the (T515) Transmission Control Relay Control circuit in the Transmission Control Relay connector.
Is the voltage above 1.0 volts?
Yes
Repair the (T515) Transmission Control Relay Control circuit for a short to voltage.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
Go To 7
7. CHECK THE (T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT FOR AN OPEN
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Measure the resistance of the (T515) Transmission Control Relay Control circuit between the Transmission Control Relay connector and the PCM C2 harness connector.
Is the resistance below 5.0 ohms?
Yes
Go To 8
No
Repair the (T515) Transmission Control Relay Control circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
8. CHECK THE (T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT SHORT TO GROUND
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Measure the resistance between ground and the (T515) Transmission Control Relay Control circuit in the Transmission Control Relay connector.
Is the resistance above 100k ohms?
Yes
Go To 9
No
Repair the (T515) Transmission Control Relay Control circuit for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
9. CHECK THE (T515) TRANSMISSION CONTROL RELAY CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
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Measure the resistance between the Transmission Control Relay Control circuit and all other circuits in the PCM C2 harness connector.
Is the resistance below 100k ohms between the (T515) Transmission Control Relay Control circuit and any other circuit(s) in the PCM C2 harness connector?
Yes
Repair the Transmission Control Relay Control circuit for a short to another circuit(s).
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
Go To 10
10. CHECK THE POWERTRAIN CONTROL MODULE
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Turn the ignition off to the lock position.
Ignition on, engine not running.
With the scan tool, actuate the Transmission Relay.
Using a 12-volt test light connected to 12-volts, check the Transmission Control Relay Control circuit in the Transmission Control Relay Control connector.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the Test Light cycle on and off and illuminate brightly?
Yes
Go To 11
No
Using the schematics as a guide, check the Powertrain Control Module (PCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM per the Service Information. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/POWERTRAIN CONTROL MODULE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
11. INTERMITTENT WIRING AND CONNECTORS
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The conditions necessary to set this DTC are not present at this time.
Use the Freeze Frame Data to help duplicate the conditions in which the DTC originally set. Pay particular attention to the DTC set conditions, such as, VSS, MAP, ECT, and Load
Using the schematics as a guide, visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
Wiggle the wiring and connectors while checking for any possible open or shorted circuits.
Check for any Service Information Tune-ups or Technical Service Bulletins that may apply.
Were there any problems found?
Yes
Repair as necessary.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
Test Complete.