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MIL On/Loss of Engine Power

Group Ref.: Chassis/Body Electrical

Bulletin No.: 438115

Date: May, 1994

SUBJECT:
MALFUNCTION INDICATOR LAMP (SERVICE ENGINE SOON) ON AND/OR LOSS OF ENGINE POWER (INSPECT/REROUTE ENGINE HARNESS)

MODELS:
1994 CADILLAC CONCOURS (BEFORE VIN BREAKPOINT 266253)
ELDORADO (BEFORE VIN BREAKPOINT 615542)
SEVILLE (BEFORE VIN BREAKPOINT 829859)

CONDITION:

Some owners may comment on Malfunction Indicator Lamp (Service Engine Soon) on and/or loss of engine power.

CAUSE:

The Northstar engine harness may have been routed over the engine/transmission mounting bracket in the area near the power steering gear. This routing permits the harness to contact the exhaust system, which could eventually wear through the wiring insulation.

Contact of the Northstar engine harness with the exhaust manifold could cause one or more of the following conditions:

1. Malfunction Indicator Lamp (Service Engine Soon) on, along with one or more diagnostic codes set.

2. Loss of engine power, a result of an open engine ground G102.

CORRECTION:

Determine if the engine harness routing is correct and reroute harness as follows:
1. Disconnect negative battery cable.
2. Position vehicle so that the lower engine area behind the right front wheel is accessible. No disassembly is required to gain this access.








3. Examine the lower front corner of the engine near the transmission mount assembly. In this area, a branch of the engine harness routes below the heater inlet/outlet pipes. From there, it proceeds downward and splits into four component branches. These branches go to: (1) engine ground G102, (2) knock sensor, (3) vehicle speed sensor, and (4) power steering pressure switch. Check that these branches are routed as shown in Figures 1, 2 and 3. The harness and all four branches of the harness should be below the transmission mounting bracket, with the power steering pressure switch branch threaded through the transmission mount bracket.

4. If the engine harness was installed in any manner other than the way shown in Step 3, inspect the harness for damage.

5. If the engine harness is damaged, repair the wiring.

6. If the engine harness routing differs from the configuration described in Step 3, reroute the harness as follows.

7. Unplug the power steering pressure switch connector, knock sensor connector and vehicle speed connector.

8. Disconnect the engine ground G102 located near the engine knock sensor by removing one bolt.

9. Reroute the engine harness as described in Step 3 above (Figures 1, 2 and 3).

10. Install engine ground and secure to engine using bolt. Tighten bolt to 11 N-m (8 lbs.ft.).
11. Connect the vehicle speed sensor connector, knock sensor connector and power steering pressure switch connector.
12. Reconnect negative battery cable.

WARRANTY INFORMATION:

For vehicles repaired under warranty, use:

Labor Operation Labor Time
0.2 hr.