Trouble code #51

My daughter tried to smog her 89 camry but we got error code 51. Anyone know what that is? Thanx in advance--K

Word for word from a 83-91 Camry Haynes manual: Air conditioner switch ON, idle switch OFF or shift position other than P or N range during diagnosis check. This is from a chart labeled "Trouble code chart for all 87 through 1990 vehicles (four-cylinder engines)".

If you have a six cyl engine it means: No "IDL" signal, "NSW" or A/C signal to ECU, with the check terminals E1 and TE1 shorted.

Tell us which engine you have and I'll explain further if needed.

She has the v-6. I think that after 18 years the car may be giving up the ghost. She took it for smog, failed due to timing. Took it to smog repair station, timing adjusted. By the time she got back to smog check, timing was ok but idle was off. Went back to smog repair station but idle was within normal limits ( I don't have the specific numbers) By then she was done so I had to follow up on it. I just wasn't sure if they were jacking me around. This smog business can be very frustrating to say the least.