Test TC-29A - Injector Control Circuits (DTC 27)

1984 Plymouth Horizon Base, 1.6 ASECTION Test TC-29A - Injector Control Circuits (DTC 27)
WARNING: This page is about a different car, the 1994 Eagle Vision, 1994 Dodge Intrepid, 1994 Chrysler New Yorker, 1994 Chrysler LHS, and 1994 Chrysler Concorde. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit & connector terminal identification, see CONNECTOR IDENTIFICATION DIRECTORY TABLE  . For wiring diagrams, see WIRING DIAGRAMS  section. After each repair, perform TEST VER-2  .
  1. Using DRB, erase trouble codes. Attempt to start engine. If necessary, crank engine for at least 10 seconds. Using DRB, read trouble codes. Allow engine to idle for at least 20 seconds. If DRB displays any injector control circuit codes, see INJECTOR CONTROL CIRCUIT CODES table and perform corresponding test. If DRB does not display any injector control circuit codes, go to next step.
    INJECTOR CONTROL CIRCUIT CODES

    DRB Display Test No.
    Control Circuit
    Injector No. 1 TC-29D 
    Injector No. 2 TC-30C 
    Injector No. 3 TC-31C 
    Injector No. 4 TC-32C 
    Injector No. 5 TC-33C 
    Injector No. 6 TC-34C 
  2. At this time, the condition required to set trouble code is not present. INJECTOR CONTROL CIRCUIT trouble code sets when Powertrain Control Module (PCM) does not detect injector turn off edge when expected. Possible causes are: open or shorted injector control circuit, open power supply, open injector, or failed driver in PCM.
  3. Inspect wiring and connectors. Repair as required. If wiring and connectors are okay, start engine. Wiggle wiring harness and connectors from injector to PCM. If engine misses or stalls when wiring harness and connectors are wiggled, repair area where wiggling caused problem to appear. If engine does not miss or stall when wiring harness and connectors are wiggled, see INACTIVE TROUBLE CODE CONDITION  this article. Test is complete.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.