Loss of Power Steering Assist, Power Steering Warning Message Displayed in DIC, IPC/Radio Displays Erratic, DTC C0900, B1325 Set (Replace Ignition Coil/Module Assembly and Add Ground Strap)

Some customers may comment on a loss of power steering assist at high RPM (above 3500 RPM) and a power steering warning message displayed in the DIC. They may also comment some instrument/radio displays are erratic.

Upon investigation, the technician may find DTC C0900 set. If the displays were erratic, then DTC B1325 will also be set.

This condition may occur when the system voltage exceeds 16 volts for one second for code C0900 and the system shuts down to protect it from over-voltage operation. If the voltage exceeds 18 volts for five seconds for code B1325, then other electronic systems protect themselves and shut down. It has been found that this voltage increase is caused by an interaction between the alternator and the ignition coil/module assembly.

Replace the ignition coil/module assembly and add ground strap following the procedure below.

1. Disconnect the ignition coil electrical connector.
2. Disconnect the left side spark plug wires from the ignition coil.
3. Disconnect the right side spark plug wires from the ignition coil.
4. Remove the four bolts attaching the ignition coil to its mounting bracket and remove the ignition coil.
5. Remove the ignition coil from the mounting bracket.
6. Loosen the two lower ignition coil mounting bracket nuts.
7. Remove the two upper ignition coil mounting bracket bolts and discard.



8. Install the ground strap (1), P/N 12581176, to the upper left side of the bracket as shown between the coil bracket and intake. Install the new bracket bolt, P/N 11570082, (do not tighten at this time). Prior to installing the ground strap, remove the captured nut and washers. They are not needed (simply pound them out with a hammer on a vise).
9. Install the washer (2), P/N 02436162, to the upper right side of the bracket between the coil bracket and intake. Install the new bracket bolt, P/N 11570082, (do not tighten at this time).

Tighten
Tighten all the ignition coil bracket bolts and nuts to 25 N·m (15 lb ft).

10. Install the new ignition coil to the mounting bracket.



11. Install the other end of the ground strap to the coil as shown and secure using a new bolt, P/N 11588715.
12. Install the other three ignition coil bolts.

Tighten
Tighten the bolts to 10 N·m (89 lb in).

13. Connect the right side spark plug wires to the ignition coil.
14. Connect the left side spark plug wires to the ignition coil.
15. Connect the ignition coil electrical connector.

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