Signal Too Low. Permanent Fault

Other diagnostic trouble codes (DTCs)
Read off other diagnostic trouble codes (DTCs). Are any of the diagnostic trouble codes (DTCs) EFI-153, EFI-212, EFI-242, EFI-447, EFI-521, EFI-541 or EFI-614 stored?

Yes:
^ Proceed to Verification in Signal Too Low. Permanent Fault
No:
^ Proceed to Checking power cable section below.





Checking fuse
Check that fuse 11B/5 is intact. Is the fuse intact?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking for a short-circuit section below.








Checking voltage to fuse
- Ignition on.
- Remove fuse 11B/5.

Connect a voltmeter between the left output on the fuse 11B/5 fuse holder and ground.
The voltmeter should read battery voltage.

If reading is OK:
^ Proceed to Checking for an open-circuit section below.

If reading is incorrect:
^ Proceed to Checking for an open-circuit section below.








Checking for a short-circuit
Check circuit after fuse 11B/5 for a short-circuit to ground. Then continue with: ^ Verification section below.




Checking for an open-circuit
Check cable between fuse 11 B/5 and main relay (2/32) terminal 3 for an open-circuit.

Then continue with:
^ Verification section below.











Checking power cable
- Ignition off.
- Disconnect the pulsed secondary air injection system (PAIR) pump relay from the relay base.
- Ignition on.

Connect a voltmeter between relay base terminal 2 and ground.
The voltmeter should read battery voltage.

If reading is OK:
^ Verification section below.

If reading is incorrect:
^ Proceed to Checking for an open-circuit section below.











Checking signal cable resistance
- Ignition off.
- Pulsed secondary air injection system (PAIR) pump relay disconnected.

Connect an ohmmeter between relay base terminal 4 and ground.
The ohmmeter should read infinite resistance.

If reading is OK:
^ Proceed to Checking the signal cable section below.

If reading is incorrect:
^ Proceed to Checking for a short-circuit section below.





Checking for an open-circuit
Check cable between fuse 11B/5 and pulsed secondary air injection system (PAIR) pump relay (2/53) terminal 2 for an open-circuit.

Then continue with:
^ Verification section below.














Checking the signal cable
- Ignition off.
- Pulsed secondary air injection system (PAIR) pump relay disconnected.
- Connect the breakout box and check ground terminals.

Connect an ohmmeter between terminal #38 (B38) on the breakout box and relay base terminal 4.
The ohmmeter should read approx. 0 ohm.

If reading is OK:
^ Proceed to Checking pulsed secondary air injection system (PAIR) pump relay section below.

If reading is incorrect:
^ Proceed to Checking for an open-circuit section below.





Checking for a short-circuit
Check signal cable between pulsed secondary air injection system (PAIR) pump relay terminal 4 and engine control module (ECM) #B38 for a short-circuit to ground.

Then continue with:
^ Verification section below.








Checking pulsed secondary air injection system (PAIR) pump relay
- Ignition off.
- Reconnect pulsed secondary air injection system (PAIR) pump relay.
- Ignition on.

Activate pulsed secondary air injection system (PAIR) pump. Does the pulsed secondary air injection system (PAIR) pump start?

Yes:
^ Proceed to Checking for contact resistance and oxidation section below.

No:
^ Proceed to Replacing component section below.





Checking for an open-circuit
Check signal cable between pulsed secondary air injection system (PAIR) pump relay terminal 4 and engine control module (ECM) #B38 for an open-circuit.

Then continue with:
^ Verification section below.

Checking for contact resistance and oxidation
The cause of the diagnostic trouble code (DTC) has been loose connections in the pulsed secondary air injection system (PAIR) pump relay connectors. Check connectors for contact resistance and oxidation and remedy.

Then continue with:
^ Verification section below.





Replacing component
Try a new pulsed secondary air injection system (PAIR) pump relay.

^ Proceed to next step below.








Verification

Hint: After carrying out the repair check that the fault has been remedied.

- Ignition on.
- Activate pulsed secondary air injection system (PAIR) pump. A "clicking sound" should be heard from the relay and the pulsed secondary air injection system (PAIR) pump should start.

If reading is OK:
^ Fault corrected

If reading is incorrect:
^ Fault not found