DTC 134

EAL. Code 1-3-4

1-3-4 Incorrect load signal

DTC information

Conditions for DTC






The load signal (TQ) from the Engine Control Module (ECM) provides information to the transmission control module (TCM) on the torque being delivered by the engine. This signal also passes on data about the engine speed (rpm), and whether the engine is idling or is without fuel. If the TCM does not register an incoming load signal when the RPM sensor on the transmission gives a signal that the input shaft rpm is over approx. 600 mm after the torque converter, the DTC 1-3-4 is set.

Substitution value

Control Module GROUP I:
No substitution value

Control Module GROUP II:
The transmission control module (TCM) "Emergency mode I" program is initiated.

Defect cause

- Break in signal wiring
- Short circuit to supply or ground in the signal wiring.
- Contact resistance in connections.

Fault symptom

- No lock-up (Emergency mode I).
- Fault-tracing starts with EAL1.


EAL1

Checking signal wiring resistance to ground






- Ignition OFF
- Connect test box and check ground points as per GB1-GB2 GB. Connecting the Test Box

- Disconnect TCM
- Disconnect the Engine Control Module (ECM)

Use an ohmmeter to measure between #42 (#B1 2) and #20 (#A20) on the test box.
The ohmmeter should read infinite resistance.






If reading is OK:
- Checking signal wiring resistance EAL2.

If reading is incorrect:
- Check the cable between the TCM #B12 and the ECM module #B12 for Fenix 5,2, LH 3,2/EZ129K Motronic 4,3 for short circuit to ground as per FA3. FA. Checking Wiring and Connections

- On cars with ECM LH 3,2/EZ129K, also check the cable between ECM module LH 3,2 #B12 and ECM module EZ129K #B12 for short circuit to ground as per FA3.



EAL2

Checking signal wiring resistance

- Ignition OFF
- Test box connected
- Transmission control module (TCM) disconnected
- Connect a test box to the engine control module (MFI Fenix 3.2, LH 3.2, or Motronic 4.3).

- Engine Control Module ECM disconnected.






Connect ohmmeter between TCM test box #42 (#B12)and the ECM test box:

- #12 (#B12) for Fenix 5.2 and Motronic 4.3 MFI ECM
- #42 (#B12) for LH 3,2 MFI ECM.

The ohmmeter should read approx. 0 Ohms.







If reading is OK:
- Checking control signal wiring for short circuit to battery voltage EA L3.

If reading is incorrect:
- Check the cable between the TCM #B12 and the ECM #B12 for Fenix 5.2, LH 3.2/EZ129K or Motronic 4.3 for breaks as per FA2. FA. Checking Wiring and Connections



EAL3

Checking signal wiring for short circuit to battery voltage







- Ignition OFF
- Engine Control Module test box disconnected
- Connect the control modules
- Ignition ON.

Use a voltmeter to measure between #42 (#B12) and #20 (#A20) on the transmission test box.
The voltmeter should register:

- Fenix 5,2 approx. 1-2 V below battery voltage.
- LH 0 approx. 3,2 V
- Motronic 4.8 approx. 0.8 V.

If reading is OK:
- Checking load signal EAL4.

If reading is incorrect:
- Check the cable between the TCM #B12 and the ECM module #B12 for Fenix 5.2, LH 3.2/EZ129K, or Motronic 4.3 for short circuit to supply as per FA4. FA. Checking Wiring and Connections

- On cars with engine management systems type ECM LH 3.2/EZ129K, also check the cable between ECM LH 3.2 #B12 and ECM EZ129K #B12 for short circuits to supply as per FA4.



EAL4

Checking load signal






- Ignition OFF
- Test box connected to TCM
- Control modules connected

Connect meter and measure frequency between #42 (#B12) and #20 (#A20) on the test box.

- Engine idling






The frequency should be approx. 34 Hz with engine at normal operating temperature.

If reading is OK:
- Checking Transmission Control Module (TCM) EAL6.

If reading is incorrect:
- Checking Engine Control Module (ECM) EAL5.



EAL5

Checking Engine Control Module (ECM)






- Ignition OFF
- Try with a new engine control module (MFI Fenix 5.2, LH 3.2, Motronic 4.3)
- New ECM connected.

Connect meter and measure frequency between #42 (#B12) and #20 (#A20) on the test box.

- Engine idling






The frequency should be approx. 34 Hz with engine at normal operating temperature.

If reading is OK:
- The old ECM is defective.

If reading is incorrect:
- The old ECM is OK. Reinstall the old ECM.
- Then continue with: Checking Transmission Control Module TCM EAL6.



EAL6

Checking the Transmission Control Module (TCM)






- Ignition OFF
- Reconnect connectors etc.
- Clear DTCs

Test drive the car as per Test Drive Form. Test Aide Drive Form






If the DTC does not recur:
- Intermittent fault. Fault-tracing as per EAL7.

If the DTC is set again:
- Try a new TCM as per AB1-AB4.



EAL7

Intermittent Fault.

Checking wiring and connections






- Check the connectors for the ECM and the TCM for loose connections as per FA5, and contact resistance and oxidation as per FA6. FA. Checking Wiring and Connections

- Check the cable between the TCM #812 and the ECM for Fenix 5.2, LH 3.2/EZ129K, or Motronic 4.3 for intermittent break as per FA2, intermittent short circuit to ground as per FA3 and intermittent short circuit to supply as per FA4.

- On cars with engine control module (ECM) Systems type LH 3.2/EZ129K, also check the cable between ECM LH 3.2 #B12 and ECM EZ129k #B12 for intermittent short circuits to ground FA3 and intermittent short circuit to supply as per FA4. FA. Checking Wiring and Connections