DTC 66 Delivered Engine Torque Circuit Malfunction. Cadillac Catera 1997

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 1997 🢒 Catera 🢒 DTC 🢒 DTC 66 Delivered Engine Torque Circuit Malfunction

ABS Components
Antilock Brake System Schematics

Circuit Description

The traction control system uses the ECM fuel controls and uses the ignition controls to limit drive wheel slippage during acceleration. The ECM reduces engine torque by retarding spark timing, and/or shutting off up to three injectors. The EBTCM sends a torque request to the ECM via a Pulse Width Modulated (PWM) signal requesting the desired torque level for proper traction control system operation. The ECM then provides a delivered torque PWM signal informing the EBTCM how much actual torque is produced by the engine.

Conditions for Setting the DTC

•	After initialization and after 2 seconds have past, the EBTCM does not receive a minimum of 2 signals within 100 milliseconds of each other.

•	There is an open in the circuit.

•	There is a short to ground in the circuit.

•	There is a short to voltage in the circuit.

Action Taken When the DTC Sets

•	A malfunction DTC is stored.

•	The TC indicator lamp is turned on.

•	The TCS is disabled.

•	The ABS remains functional.

Conditions for Clearing the DTC

•	The condition for the DTC is no longer present.

•	The scan tool Clear DTCs function is used.

•	100 drive cycles have passed with no DTCs detected.

Diagnostic Aids

The following can cause an intermittent malfunction:

•	A poor connection may cause an intermittent malfunction.

•	Rubbed through wire insulation may cause an intermittent malfunction.

•	A wire that is broken inside the insulation may cause an intermittent malfunction.

Check for the following in any circuit suspected of causing an intermittent malfunction:

•	Check for backed out terminals.

•	Check for improper mating.

•	Check for broken locks.

•	Check for improperly formed terminals.

•	Check for damaged terminals.

•	Check for poor terminal to wiring connections.

•	Check for physical damage to the wiring harness.

Perform a thorough inspection of the wiring. Perform a thorough inspection of the connectors. Failure to carefully and fully inspect the wiring and the connectors may result in misdiagnosis. Misdiagnosis causes part replacement with reappearance of the malfunction.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

It is very important to check ground G103. Corrosion or a loose connection at this point may cause a malfunction in the PWM signal.

The scan tool can be used to check the delivered engine torque signal from the Engine Control Module. It should fluctuate up and down with throttle movement.

This test checks the presents of a pull-up voltage from the EBTCM.

DTC 66 - Delivered Engine Torque Circuit Malfunction

Step

Action

Value(s)

Yes

Was the Diagnostic System Check performed?

Go to Step 2

Go to A Diagnostic System Check

Check that ground G103 is clean and check that ground G103 is torqued to the proper specifications. Refer to Ground Distribution in Wiring Systems for ground specifications and ground locations.

Are the following signs evident:

•	Is the ground loose?

•	Is the ground damaged?

•	Is the ground corroded?

Go to Step 18

Go to Step 3

Turn the ignition switch to the OFF position.
Install a scan tool.
Start the engine.
Use the scan tool to select Data Display.
Momentarily press the accelerator while the engine is running.
Observe the Delivered Engine Torque.

Did the percent of delivered torque fluctuate within the specified range?

20-60 %

Go to Step 6

Go to Step 4

Turn the ignition switch to the OFF position.
Disconnect the ECM connector.
Disconnect the TCM connector.
Turn the ignition switch to the RUN position with the engine off.
Use a J 39200 DMM to measure the voltage between the ECM harness connector terminal 83 and ground.

Is the voltage measured equal to or greater than the specified voltage?

10 V

Go to Step 5

Go to Step 7

Turn the ignition switch to the OFF position.
Disconnect the 25-way EBTCM connector C1.
Install a J 39700 Universal Breakout Box with a J 39700-250 Cable Adapter to the EBTCM harness connector only.
Turn the ignition switch to the RUN position with the engine off.
Use a J 39200 DMM to measure the voltage between the J 39700 terminal 5 and ground.

Is the voltage measured within the specified range?

0-2 V

Go to Step 9

Go to Step 12

Turn the ignition switch to the OFF position.
Inspect the following:

•	Inspect the delivered engine torque circuit for signs of damage which may result in the following:

-	Inspect for an intermittent open.

-	Inspect for an intermittent short to ground.

-	Inspect for an intermittent short to voltage.

•	Inspect the 25-way EBTCM harness connector C1, terminal 5 for signs of damage which may result in the following:

-	Inspect for an intermittent open.

-	Inspect for an intermittent short to ground.

-	Inspect for an intermittent short to voltage.

•	Inspect the ECM harness connector terminal 83 for signs of damage which may result in the following:

-	Inspect for an intermittent open.

-	Inspect for an intermittent short to ground.

-	Inspect for an intermittent short to voltage.

•	Inspect the TCM harness connector terminal 44 for signs of damage which may result in the following:

-	Inspect for an intermittent open.

-	Inspect for an intermittent short to ground.

-	Inspect for an intermittent short to voltage.

Inspect the remaining terminals of the 25-way EBTCM harness connector C1 for the following signs:

•	Inspect for signs of damage.

•	Inspect for signs of poor terminal contact.

•	Inspect for signs of terminal corrosion.

Are the following signs evident:

•	Is poor terminal contact evident?

•	Is corrosion evident?

•	Is damage evident?

Go to Step 15

Go to Step 11

Turn the ignition switch to the OFF position.
Disconnect the 25-way EBTCM connector C1.
Install a J 39700 Universal Breakout Box with a J 39700-250 Cable Adapter to the EBTCM harness connector only.
Use a J 39200 DMM to measure the resistance between the J 39700 terminal 5 and the ECM harness connector terminal 83.

Is the resistance within the specified range?

0-2 ohms

Go to Step 8

Go to Step 13

Use a J 39200 DMM to measure the resistance between the J 39700 terminal 5 and ground.

Is the resistance within the specified range?

OL (Infinite)

Go to Step 19

Go to Step 14

Turn the ignition switch to the OFF position.
Inspect the 25-way EBTCM harness connector C1, terminal 5 and inspect the ECM harness connector terminal 83 for the following signs of damage:

•	Inspect for poor terminal contact.

•	Inspect for terminal corrosion.

Inspect the remaining terminals of the 25-way EBTCM harness connector C1 for the following signs of damage:

•	Inspect for poor terminal contact.

•	Inspect for terminal corrosion.

Are the following signs evident:

•	Is poor terminal contact evident?

•	Is corrosion evident.

•	Is damage evident?

Go to Step 15

Go to Step 10

Reconnect the ECM connector.
Reconnect the TCM connector.
Reconnect the 25-way EBTCM connector C1.
Test drive the vehicle over 6 km/h (4 mph) for 30 seconds.
Use the scan tool to read the DTCs.

Did DTC 66 reset?

Go to Step 16

Go to Step 17

Reconnect the ECM connector.
Reconnect the TCM connector.
Reconnect the 25-way EBTCM connector C1.
Test drive the vehicle over 6 km/h (4 mph) for 30 seconds.
Use the scan tool to read the DTCs.

Did DTC 66 reset?

Go to Step 19

Go to Step 17

Repair the short to voltage in the delivered engine torque circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to A Diagnostic System Check

Repair an open or repair a high resistance in the delivered engine torque circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to A Diagnostic System Check

Repair a short to ground in the delivered engine torque circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to A Diagnostic System Check

Replace all the terminals or replace the connectors that exhibit signs of the following:

•	Replace the connectors that exhibit poor terminals.

•	Replace the connectors that exhibit terminal corrosion.

•	Replace the connectors that exhibit damage.

Refer to Connector Repairs or Repairing Connector Terminals in Wiring Systems.

Is the repair complete?

Go to A Diagnostic System Check

Suspect ECM. Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

Is the diagnosis complete?

Go to A Diagnostic System Check

The malfunction is intermittent or the malfunction is not present at this time. Refer to Diagnostic Aids for more information.

Is the diagnosis complete?

Go to A Diagnostic System Check

Repair the ground as necessary. Refer to Wiring Repairs in Wiring Systems if the ground terminal requires replacement.

Is the repair complete?

Go to A Diagnostic System Check

Replace the EBTCM. Refer to EBTCM Replacement .

Is the repair complete?

Go to A Diagnostic System Check