1991 Honda Accord dash lights flashing?

Question

Where is the cpu that controls the dash lights and Speed odometer. There is one cpu under the passenger seat that controls the seat belts another on the passenger side under the carpet that controls the sport light and transmission's shifting.

Do any of these control the speedometer or other dash lights?

Answer 1

In all probability you have a weak or undercharged battery.  that may be caused by a loose alternator belt or the battery itself.  

The flickering or dimming happens when the battery is supplying most of the current for the electrical load instead of the alternator

Since the early ’90s, Honda vehicles have come with an electrical load detector (ELD) unit in the under-hood fuse/relay box. This unit allows the ECM/PCM to regulate the alternator (switch it between high output and low output) to provide the best combination of fuel economy and electrical system operation. The ELD sends a signal to the ECM/PCM that’s proportional to the electrical demand. The ECM/PCM switches the alternator between high output and low output depending on several factors, which include electrical demand, battery charge level, and the driving cycle. When the alternator is in low output, the engine load is reduced and fuel economy improves.

If the battery and alternator belt are okay, chances are the flickering or dimming isn’t an electrical problem but rather the switching altrnator output due to the operation of the ELD.