P1631

DIAGNOSTIC TROUBLE CODES P1631, P1632
Fuel pump relay, output from control module low/high
No continuity or shorting to ground/batt+

NOTE: Refer to "Relays" at "Computers and Control Systems/Description and Operation" for a description of how the fuel pump relay works. Relays

Diagnostic Procedures.
Check operation of the relay as follows:
1. Run the starter motor and check whether current is present at fuses 32 (fuel pump) and 38 (oxygen sensor preheater).

If current is present at the fuses, the relay has operated.
If it releases when the engine stops, relay operation is OK.
If no current is present at the fuses, continue with the next step.

2. Lower the relay holder under the dashboard.
Turn the ignition switch to the DRIVE position and connect a jumper lead between ground and pin 85 of the relay.
Check whether the relay has been energized. To do this, check whether current is present at fuses 38 and 32.

If the relay operates, proceed to step 4.
If the relay does NOT operate, continue with step 3.

3. Check whether battery voltage is applied to pin 86 of the relay from pin 87 of the main relay, and whether it is applied to pin 30 of the relay from maxi-fuse 2.

If it is NOT, check the wiring for continuity/shorting.
If voltage is present on pins 30 and 86, remove the relay and check whether the resistance across pins 85 and 86 is 60 ohms.
If it is not, change the relay.

4. If the relay works when a jumper lead is connected from ground to pin 85 but not when the starter motor is engaged, check the lead between pin 85 of the relay and pin 3 of the control module for continuity.

If the lead is OK, continue at "Before Control Module Replacement" for further diagnostic instructions. Before Replacing A Control Module