MIL ON - DTC PO411 Secondary Air Injection System

18-47
Amended
4/95

Secondary Air Injection (AIR) -
DTC P0411 - Repair Procedure

MODEL
All (4.0L) 1995 MY
Sedan (4.0L) Range VIN 720001 - 734672
XJS (4.0L) Range VIN 194774 - 199153

DATE: 3/95

Remove and destroy Bulletin 18-47, Date 3/95.
Replace with this Bulletin.
Revisions are marked with asterisks.

ISSUE:

The CHECK ENGINE MIL illuminates with no loss of power on 1995 MY vehicles within the VIN ranges listed below. Diagnosis with PDU indicates that DTC P0411 is stored in memory.

Sedan (4.0L) Range VIN *720001-734672*

XJS (4.0L) Range VIN *194774-199153*

At the end of the secondary air injection cycle, vacuum may become trapped in the hose from the air pump (AIRP) to the secondary air injection check valve (AIRC). The trapped vacuum will not allow the AIRP solenoid operated stop valve (integral with the AIRP) to open during the next air injection cycle. The ECM monitors no drift in the HO2S swings, which triggers the CHECK ENGINE MIL.

A revised air pump hose with a vacuum bleed is fitted to all AJ16 engines in production from VIN *734673* (Sedan [4.0L] Range) and VIN *199154* (XJS [4.0L] Range).

ACTION:

If 1995 MY vehicles within the VIN ranges listed above illuminate the CHECK ENGINE MIL with DTC P0411 stored in the ECM memory, perform the following procedure.

CHECK ENGINE MIL ILLUMINATED WITH DTC P0411 - REPAIR PROCEDURE

1. Diagnose the AIR system following the instructions in the XJ6 - XJ12 Electrical Diagnostic Manual 1995 MY Volume 1, Section 5.1, pages 271-272.

2. Repair any faults found.

3. If no fault is found, clear DTC P0411.

4. Replace the existing AIRP to AIRC hose with a new hose (normally aspirated engines part number NBC 4798AA, supercharged engines part number NBD 4798AA).

NOTE:
Continue to report all DTCs by completing form S-93 and forwarding to Jaguar Cars Product Investigations.

PARTS INFORMATION:

DESCRIPTION PART NUMBER QTY

Air pump hose - AJ16 normally aspirated NBC 4798AA 1

Air pump hose - AJ16 supercharged NBD 4798AA 1

WARRANTY INFORMATION:

FAULT CODE R.O NUMBER DESCRIPTION TIME ALLOWANCE
BG ZB ZZ 17.91.29 Air injection hose-Renew 0.10 hrs.