SsangYong Musso. Manual - part 168

1F-256 ENGINE CONTROLS

SSANGYONG Y158

Circuit Description

The Engine Control Module (ECM) has six (four-2.3L
DOHC) individual injector driver circuits, each of which
controls an injector. When a driver circuit is grounded
by the ECM, the injector is activated. The ECM monitors
a voltage drop through a fixed resistor and controls it.
The voltage on each driver is monitored to detect a fault.
If the voltage is not what the ECM expects to monitor
on the circuit, a Diagnostic Trouble Code (DTC) is set.
This DTC detects a short to ground and/or an open
circuit conditions for low-side drive injector outputs.

Conditions for Setting the DTC

•••••

Voltage is less than 1/3 of battery voltage for ground.

•••••

Voltage is less than 2/3 of battery voltage for open.

Action Taken When the DTC Sets

•••••

The MIL will illuminate after two consecutive driving
cycles in which the diagnostic runs with the fault ac-
tive.

•••••

The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored in
the Freeze Frame and Failure Records buffers.

•••••

A history DTC is stored.

DIAGNOSTIC TROUBLE CODE (DTC) P0261

INJECTOR 1: SHORT CIRCUIT TO GROUND OR OPEN

Conditions for Clearing the MIL/DTC

•••••

The MIL will turn off after three consecutive driving
cycles in which the diagnostic runs without a fault.

•••••

A history DTC will clear after 40 consecutive warm-
up cycles without a fault.

•••••

The DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

An injector driver circuit that is open or shorted to ground
will cause a DTC P0261 to set. It will also cause a mis-
fire due to an inoperative injector. A misfire DTC should
also be set indicating which injector is inoperative.

The injector resistance tested at the ECM connection
is slightly more than if tested directly at the injector be-
cause it includes resistance of the harness wires. The
normal value is about 14.5 - 15

Ω

YAB1F170

ENGINE CONTROLS 1F-257

SSANGYONG Y158

Perform the Euro On-Board Diagnostic (EOBD) System
Check.
Is the system check complete?

Will the engine start?

1. Turn the ignition ON, with the engine OFF.
2. Install a scan tool and clear the Diagnostic Trouble

Codes (DTCs).

3. Start the engine and idle for one minute.
Does DTC P0261 reset?
1. Turn the ignition ON, with the engine OFF.
2. Review the Freeze Frame data and note the

parameters.

3. Operate the vehicle within the Freeze Frame

conditions as noted.

Does the DTC P0261 reset?
1. Turn the ignition OFF.
2. Disconnect the Engine Control Module (ECM) (gray)

connector for injector 1.

3. Turn the ignition ON, with engine OFF.
4. With a test light connected to ground, probe the

driver circuit, terminal 63.

Does the test light illuminate?
Repair the short to ground or open in the injector driver
circuit.
Is the repair complete?
Check the connections at the ECM and repair as
necessary.
Is the repair complete?
1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?

Step

Action

Value(s)

Yes

DTC P0261 Injector 1: Short Circuit to Ground or Open

Go to Step 2

Go to “Euro

On-Board

Diagnostic

System Check”

Test Description

The number(s) below refer to specific step(s) on
thediagnostic table.

1. Euro On-Board Diagnostic (EOBD) System Check

prompts the technician to complete some basic
checks and store the freeze frame and failure
records data on the scan tool if applicable. This
creates an electronic copy of the data taken when
the malfunction occurred. The information is then
stored on the scan tool for later reference.

3. This step determines if DTC P0261 is the result of

a hard failure or an intermittent condition.

5. This step tests the wiring harness and the ECM

control of the injectors using a test light.

8. The replacement ECM must be reprogrammed. Re-

fer to the latest Techline procedure for ECM repro-
gramming.

Go to Step 5

Go to Step 4

Go to Step 7

Go to Step 6

Go to Step 9

Go to Step 8

Go to Step 9

Go to Step 3

Go to “Engine

Cranks But Will

Not Run”

Go to Step 9

Go to Step 5

Go to

“Diagnostic

Aids”

1F-258 ENGINE CONTROLS

SSANGYONG Y158

Step

Action

Value(s)

Yes

1. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating

temperature.

3. Operate the vehicle within the conditions for setting

this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic ran and
passed?
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?

Go to Step 10

Go to Step 3

DTC P0261 Injector 1: Short Circuit to Ground or Open (Cont'd)

Go to

applicable

DTC table

System OK

ENGINE CONTROLS 1F-259

SSANGYONG Y158

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