2003 Acura 3.2TL BaseFACTORY OEM SERVICE PROCEDURE

Air Conditioning Signal: 3.5RL

  1. Turn ignition switch off. Disconnect radiator fan control unit 12-pin harness connector located under front passenger's footrest, on main wire harness. Turn ignition switch on. Measure voltage by backprobing between PCM 12-pin harness connector terminal No. 2 (Pink wire) and PCM 26-pin harness connector terminal No. 26 (Brown/Black wire). See Figure . See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. If battery voltage is not present, go to next step. If battery voltage is present, go to step  3 .
  2. Turn ignition switch off. Disconnect PCM 12-pin harness connector. Check continuity between ground and PCM 12-pin harness connector terminal No. 2 (Pink wire). If continuity is present, repair short in Pink wire between PCM 12-pin harness connector terminal No. 2 and radiator fan control unit 12-pin harness connector terminal No. 8. If continuity is not present, Cut temporary key from a non-immobilizer key blank and tape donor vehicle key to it backwards in order to deactivate immobilizer system during testing. Substitute known-good PCM, then recheck. If voltage is now as specified, replace original PCM. Recheck A/C system operation. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
  3. Turn ignition switch off. Reconnect radiator fan control unit 12-pin harness connector. Turn ignition switch on. Using a fused jumper wire, momentarily backprobe PCM 26-pin harness connector terminals No. 8 (Red/White wire) and 26 (Brown/Black wire). Repeat several times. See Figure . See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. If A/C clutch does not click, go to next step. If A/C compressor clutch clicks, go to step  5 .
  4. Locate A/C clutch relay in underhood relay box "A" at left front of engine compartment, between battery and upper radiator hose. Using a fused jumper wire, backprobe A/C clutch relay terminal No. 4 (Red/White wire) and connect to ground. Repeat several times. If A/C clutch clicks, repair open in Red/White wire between PCM 26-pin harness connector terminal No. 8 and A/C clutch relay terminal No. 4. If A/C clutch does not click, other A/C problems exist. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
  5. Start engine. Turn blower and A/C switches on. If A/C operates, A/C signal is okay. If A/C does not operate, measure voltage by backprobing between PCM 26-pin harness connector terminal No. 26 (Brown/Black wire) and PCM 12-pin harness connector terminal No. 2 (Pink wire). See Figure .
  6. If voltage is one volt or more, repair open in Pink wire between PCM 12-pin harness connector terminal No. 2 and radiator fan control unit 12-pin harness connector terminal No. 8. If voltage is less than one volt, Cut temporary key from a non-immobilizer key blank and tape donor vehicle key to it backwards in order to deactivate immobilizer system during testing. Substitute known-good PCM, then recheck. If symptom or indication goes away, replace original PCM. If not, recheck A/C system operation. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
Factory Service Tools

Use the Manual With the Right Hardware

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

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

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.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.