P1630
Code P1630, System Voltage High Or Low:
System Voltage Circuit:
CIRCUIT DESCRIPTION
The PCM monitors system voltage on CKT 439 to terminal "WC9".
DTC 1630 WILL SET WHEN:
^ The PCM detects voltage above 17 volts or below 9 volts for more than 10 seconds while the engine is running.
ACTION TAKEN (PCM will default to):
With a current DTC P1630 set, the transaxle will be forced to 3rd gear and TCC will not be allowed to engage. This is to avoid erratic shifting due to improper voltages. Also, the PCM will illuminate the MIL (Service Engine Soon).
TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Test generator output to determine proper operation of the voltage regulator. Run engine at moderate speed and measure voltage across the battery. If less than 9 or over 17 volts, diagnose alternator and voltage regulator.
DIAGNOSTIC AIDS
An intermittent may be caused by a poor connection, rubbed through insulation, a wire broken inside the insulation or poor PCM grounds.
Check for:
^ Poor connection or damaged harness - Inspect PCM harness connectors for backed out terminal "WC9" or "RB4", improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.
^ Intermittent test - Monitor SYSTEM VOLTAGE display with a Tech 1 while moving related connectors. If the failure is induced, the display will abruptly change. This may help to isolate the location of the malfunction. An engine stall while manipulating the harness indicates that the PCM has lost voltage at terminal "WC9". Check for loose connectors in CKT 439.
NOTE: Charging with a battery charger while starting the engine may set a DTC P1630.