Code No.B1856: e-Call Speaker Connection


caution When replacing the ECU, always check that the communication circuit is normal.

DIAGNOSTIC FUNCTION


If the system detects that the e-Call speaker or the door speaker (passenger’s side) is disconnected for 5 seconds or more, the e-Call control unit sets diagnosis code No. B1856.
note When diagnosis code No. B1856 is set, the e-Call switch flashes in green.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check the M.U.T.-III Diagnosis code for other.


Check if diagnosis code No.B1864 is set in the e-Call control unit.

Q. Is the diagnosis code set?

Trouble shooting diagnosis code No.B1864 (Refer to ).

Go to Step 2

STEP 2. M.U.T.-III special function.


Check the speaker (Refer to ).
Test
OK: A beep sound is heard (during the test).

Q. Is the check result normal?

Go to Step 8

NO <Item No.2> : Go to Step 3

NO <Item No.4> : Go to Step 5

NO <Item No.2 and 4> : Go to Step 7

STEP 3. Resistance measurement at between the e-Call relay box connector (ESO+ or ESO- terminals).


(1)Disconnect the e-Call relay box connector, and measure at the wiring harness side.
(2)Check the resistance between the e-Call relay box connector terminal ESO+ and ESO-.
OK: 0.9 Ω - 120 Ω
(3)Check the resistance between the e-Call relay box connector (ESO+ terminal) and body earth.
OK: No continuity

Q. Is the check result normal?

Replace the e-Call relay box (Refer to ).

Go to Step 4

STEP 4. Check of short to earth or open circuit in ESO+, ESO- line between the e-Call relay box connector and the e-Call speaker connector.


Q. Is the check result normal?

Replace the e-Call speaker (Refer to ).

Repair the connector(s) or wiring harness.

STEP 5. Resistance measurement at between the e-Call relay box connector (DSO+ or DSO- terminals)


(1)Disconnect the e-Call relay box connector, and measure at the wiring harness side.
(2)Check the resistance between the e-Call relay box connector terminal DSO+ and DSO-.
OK: 0.9 Ω - 120 Ω
(3)Check the resistance between the e-Call relay box connector (DSO+ terminal) and body earth.
OK: No continuity

Q. Is the check result normal?

Replace the e-Call relay box (Refer to ).

Go to Step 6

STEP 6. Check of short to earth or open circuit in DSO+, DSO- line between the e-Call relay box connector and the e-Call speaker connector.


Q. Is the check result normal?

Replace the door speaker (passenger’s side).

Repair the connector(s) or wiring harness.

STEP 7. Resistance measurement at between the e-Call relay box and the e-Call control unit connectors (SPO+, SPO-, ESI+ or ESI- terminals)


(1)Disconnect the e-Call control unit and e-Call relay box connector, and measure at the wiring harness side.
(2)Check the resistance between the e-Call relay box connector terminal ESI+ and body earth.
OK: No continuity
(3)Check the resistance between the e-Call relay box connector terminal ESI+ and e-Call control unit connector terminal SPO+.
OK: Continuity exists (2 Ω or less)
(4)Check the resistance between the e-Call relay box connector terminal ESI- and e-Call control unit connector terminal SPO-.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 8

Repair the connector(s) or wiring harness.

STEP 8. Check whether the diagnosis code is set again.


Check again if the diagnosis code is set in the e-Call control unit.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position, and then wait for 20 seconds.
(3)Execute "Test" on the M.U.T.-III special function.

  • Item No.4: Door speaker (Beep)
(4)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Replace the e-Call control unit (Refer to ).

Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).